differentiation-140202103726-phpapp01.ppt

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    Higher Unit 1

    www.mathsrevision.com

    Finding the gradient for a polynomial

    Differentiating a polynomial

    Differentiating Negative Indices

    Differentiating Roots

    Differentiating Brackets

    Differentiating Fraction Terms

    Differentiating with LeibnizNotation

    Exam Type Questions

    Equation of a Tangent Line

    Increasing / Decreasing functions

    Max / Min and Inflection Points

    Curve Sketching

    Max & Min Values on closed Intervals

    Optimization

    Higher Outcome 3

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    On a straight line the gradient remains constant,however with curves the gradient changes continually,and the gradient at any point is in fact the same as

    the gradient of the tangent at that point.

    The sides of the half-pipeare very steep(S) but it is

    not very steep near thebase(B).

    B

    S

    Gradients & CurvesHigher Outcome 3

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    A

    Gradient of tangent = gradient of curve at A

    B

    Gradient of tangent = gradient of curve at B

    Gradients & CurvesHigher Outcome 3

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    Gradients & Curves

    To find the gradient at anypoint on a curve we need to

    modify the gradient formulaHigher Outcome 3

    For the function y = f(x) we do this by taking the point (x, f(x))

    and another very close point ((x+h), f(x+h)).

    Then we find the gradient between the two.

    (x, f(x))

    ((x+h), f(x+h))

    True gradient

    Approx gradient

    2 1

    2 1

    -

    -

    y ym

    x x

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    The gradient is not exactly the same but is

    quite close to the actual valueWe can improve the approximation by making the value of hsmaller

    This means the two points are closer together.

    (x, f(x))

    ((x+h), f(x+h))

    True gradient

    Approx gradient

    Gradients & CurvesHigher Outcome 3

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    We can improve upon this approximation by making thevalue of heven smaller.

    (x, f(x))

    ((x+h), f(x+h))

    True gradientApprox gradient

    So the points are even closer together.

    Gradients & CurvesHigher Outcome 3

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    Higher Outcome 3

    Derivative

    We have seen that on curves the gradient changescontinually and is dependant on the position on the

    curve. ie the x-value of the given point.

    We can use the formula for the curve to produce aformula for the gradient.

    This process is called DIFFERENTIATING

    or FINDING THE DERIVATIVE

    DifferentiatingFinding theGRADIENT

    Finding the rateof change

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    If the formula/equation of the curve is given by f(x)

    Then the derivative is called f '(x) - f dash x

    There is a simple way

    of finding f '(x) from f(x).

    f(x) f '(x)

    2x2 4x4x2 8x

    5x10

    50x9

    6x7 42x6

    x3 3x2

    x5 5x4

    x99

    99x98

    DerivativeHigher Outcome 3

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    Rules for Differentiating

    These can be given by the simple flow diagram ...

    multiply by

    the power

    reduce the

    power by 1

    Or

    If f(x) = axn

    then f '(x) = naxn-1

    NB: the following terms & expressions mean the same

    GRADIENT, DERIVATIVE, RATE OF CHANGE, f '(x)

    Derivative

    Higher Outcome 3

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    com Example 5 If g(x) = 5x4- 4x5 then find g '(2) .

    g '(x) = 20x3- 20x4

    g '(2) = 20 X23- 20 X24

    = 160 - 320

    = -160

    DerivativeHigher Outcome 3

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    Your turn

    Page 91 ex 6D ( odd numbers )

    Page 92-93 ex. 6E ( even numbers )

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    Special Points

    (I) f(x) = ax, where a is any real no.

    If f(x) = ax = ax1

    then f '(x) = 1 Xax0 = aX 1 = a

    Index Laws

    x0= 1

    So if g(x) = 12x then g '(x) = 12

    Also using y = mx + c

    The line y = 12x has gradient 12,

    and derivative = gradient !!

    Higher Outcome 3

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    com (II) f(x) = a, where a is any real no.

    If f(x) = a = a X 1 = ax0

    then f '(x) = 0 X ax--1 = 0

    Index Laws

    x0= 1

    So if g(x) = -2 then g '(x) = 0

    Also using formula y = c , (see outcome1 !)

    The line y = -2 is horizontal so has gradient 0 !

    Special PointsHigher Outcome 3

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    Example 6

    h(x) = 5x2- 3x + 19 so h '(x) = 10x - 3

    and h '(-4) = 10 X (-4) - 3 = -40 - 3 = -43

    Example 7

    k(x) = 5x4- 2x3+ 19x - 8, find k '(10) .

    k '(x) = 20x3 - 6x2 + 19

    So k '(10) = 20 X 1000 - 6 X 100 + 19 = 19419

    DerivativeHigher Outcome 3

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    Find the points on the curve

    f(x) = x3- 3x2+ 2x + 7 where the gradient is 2.

    NB: gradient = derivative = f '(x)

    We need f '(x) = 2

    ie 3x2 - 6x + 2 = 2

    or 3x2

    - 6x = 0ie 3x(x - 2) = 0

    ie 3x = 0 or x - 2 = 0

    so x = 0 or x = 2

    Now using originalformula

    f(0) = 7

    f(2) = 8 -12 + 4 + 7

    = 7

    Points are (0,7) & (2,7)

    DerivativeHigher Outcome 3

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    Negative Indices

    Index Law x-m

    = 1xm

    Consider .. am Xa-m = am+(-m) = a0 = 1

    also am X 1 =

    am

    1

    This gives us the following

    NB: Before we can differentiate a term it must bein the form axn .

    Bottom line terms get negative powers !!

    Higher Outcome 3

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    Example 9f(x) = 1 =

    x2x -2

    So f '(x) = -2x-3 =-2x3

    Example 10

    g(x) = -3x4

    = -3x-4

    So g '(x) = 12x-5 = 12

    x5

    Negative IndicesHigher Outcome 3

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    Example 13

    The equation of a curve is f(x) = 8 (x 0)

    x4

    Find the gradient at the point where x = -2 .

    f(x) = 8x4 = 8x-4 so f '(x) = -32x-5 =-32x5

    Required gradient = f '(-2) = -32(-2)5

    = -32-32

    = 1

    Negative IndicesHigher Outcome 3

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    Differentiating Roots

    Fractional Indices

    x Xx = x

    x1/2 X x1/2 = x1/2+1/2 = x1 = xSo it follows that ..

    Similarly 3x = x1/3 and 4x = x1/3

    x = x1/2

    In general nx = x1/n

    Higher Outcome 3

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    so h'(y) = -7/3y-10/3 = -7

    33y10

    Example 14

    f(x) = x = x1/2 so f '(x) = 1/2x-1/2 = 1

    2x

    Example 15

    = t5/2so g'(t) = 5/2t3/2 = 5t3

    2

    Example 16

    h(y) = 13y7

    = y-7/3

    g(t) = t5

    Differentiating Roots

    Higher Outcome 3

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    Example 17

    Find the rate of change at the point where x = 4 on thecurve with equation g(x) = 4 .

    xg(x) = 4x

    = 4x-1/2

    NB: rate of change = gradient = g'(x) .

    g'(x) = -2x-3/2 = -2(x)3

    so g'(4) = -2(4)3 =

    -2

    /8 =-1

    /4 .

    Differentiating Roots

    Higher Outcome 3

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    Brackets

    Basic Rule: Break brackets before you differentiate !

    Example 18 h(x) = 2x(x + 3)(x -3)

    = 2x(x2- 9)

    = 2x3 - 18x

    So h'(x) = 6x2-18

    Also h'(-2) = 6 X(-2)2-18 = 24 - 18 = 6

    Higher Outcome 3

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    Recall 1

    7 7 7

    Fractions

    Reversing the above we get the following rule !

    This can be used as follows ..

    a + b

    c

    a b

    c c

    Higher Outcome 3

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    Example 21 (tricky)

    g(y) = (y + y)(y + 1)yy

    = (y + y1/2)(y + 1)

    y Xy1/2

    = y2 + y3/2+ y + y1/2

    y3/2

    = y2 + y3/2 + y + y1/2

    = y1/2 + 1 + y-1/2 + y-1

    y3/2 y3/2 y3/2 y3/2

    Change topowers =

    Brackets

    Singlefractions

    Correct form

    Indices

    Fractions

    Higher Outcome 3

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    srevision.com g'(y) =

    1/2y-1/2 - 1/2y-3/2 - y-2

    = 1/4 - 1/

    16 - 1/

    16 = 1/

    8

    = 1 - 1 - 1

    2y1/2 2y3/2 y2

    Also g'(4) = 1 - 1 - 12 X 41/2 2 X43/2 42

    = 1 - 1 - 12 X4 2 X(4)3 16

    Fractions

    Higher Outcome 3

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    If y is expressed in terms of x then the derivative iswritten as dy/dx .

    Leibniz Notation

    Leibniz Notation is an alternative way of expressingderivatives to f'(x) , g'(x) , etc.

    eg y = 3x2- 7x so dy/dx = 6x - 7 .

    Example 22Find

    dQ

    /dR

    NB: Q = 9R2- 15R-3

    So dQ/dR

    = 18R + 45R-4 = 18R + 45R4

    Q = 9R2

    - 15R3

    Higher Outcome 3

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    Example 23

    A curve has equation y = 5x3- 4x2+ 7 .

    Find the gradient where x = -2 ( differentiate ! )

    gradient = dy/dx = 15x2- 8x

    if x = -2 then

    gradient = 15 X(-2)2- 8 X(-2)

    = 60 - (-16) = 76

    Leibniz Notation

    Higher Outcome 3

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    Newtons 2ndLaw of Motion

    s = ut + 1/2at2 where s = distance & t = time.

    Finding ds/dt means diff in dist diff in time

    ie speed or velocity

    sods

    /dt = u + atbut ds/dt = v so we get v = u + at

    and this is Newtons 1st Law of Motion

    Real Life ExamplePhysics

    Higher Outcome 3

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    srevision.com A(a,b)

    y = mx +c

    y = f(x)

    Equation of Tangents

    tangent

    NB: at A(a, b) gradient of line = gradient of curvegradient of line = m (from y = mx + c )

    gradient of curve at (a, b) = f(a)

    it follows that m = f(a)

    Higher Outcome 3

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    Higher Outcome 3

    Equation of Tangents

    Example 24

    Find the equation of the tangent to the curve

    y = x3

    - 2x + 1 at the point where x = -1.Point: if x = -1 then y = (-1)3- (2 X-1) + 1

    = -1 - (-2) + 1

    = 2 point is (-1,2)

    Gradient: dy/dx= 3x2- 2

    when x = -1 dy/dx= 3 X(-1)2- 2

    = 3 - 2 = 1 m = 1

    Tangent is line so we need a pointplus the gradient then we can use

    the formula y - b = m(x - a) .

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    Now using y - b = m(x - a)

    we get y - 2 = 1( x + 1)

    or y - 2 = x + 1

    or y = x + 3

    point is (-1,2)

    m = 1

    Equation of Tangents

    Higher Outcome 3

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    Example 25

    Find the equation of the tangent to the curve y = 4x2

    at the point where x = -2. (x 0)Also find where the tangent cuts the X-axis and Y-axis.

    Point:when x = -2 then y = 4(-2)2

    = 4/4 = 1

    point is (-2, 1)

    Gradient: y = 4x-2 so dy/dx = -8x-3 = -8x3

    when x = -2 then dy/dx = -8

    (-2)3=-8

    /-8= 1 m = 1

    Equation of Tangents

    Higher Outcome 3

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    Now using y - b = m(x - a)

    we get y - 1 = 1( x + 2)

    or y - 1 = x + 2or y = x + 3

    Axes Tangent cuts Y-axis when x = 0

    so y = 0 + 3 = 3 at point (0, 3)

    Tangent cuts X-axis when y = 0

    so 0 = x + 3 or x = -3 at point (-3, 0)

    Equation of Tangents

    Higher Outcome 3

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    Example 26 - (other way round)

    Find the point on the curve y = x2- 6x + 5 wherethe gradient of the tangent is 14.

    gradient of tangent = gradient of curve

    dy/dx= 2x - 6

    so 2x - 6 = 142x = 20 x = 10

    Put x = 10 into y = x2- 6x + 5

    Giving y = 100 - 60 + 5= 45 Point is (10,45)

    Equation of Tangents

    Higher Outcome 3

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    Increasing & Decreasing Functionsand Stationary Points

    Consider the following graph of y = f(x) ..

    X

    y = f(x)

    a b c d e f+

    +

    +

    +

    +

    --

    0

    0

    0

    Higher Outcome 3

    I i & D i F i

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    In the graph of y = f(x)

    The function is increasing if the gradient is positive

    i.e. f (x) > 0 when x < b or d < x < f or x > f .The function is decreasing if the gradient is negative

    and f (x) < 0 when b < x < d .

    The function is stationary if the gradient is zeroand f (x) = 0 when x = b or x = d or x = f .These are called STATIONARY POINTS.

    At x = a, x = c and x = e

    the curve is simply crossing the X-axis.

    Increasing & Decreasing Functionsand Stationary Points

    Higher Outcome 3

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    Example 27

    For the function f(x) = 4x2- 24x + 19 determine theintervals when the function is decreasing and increasing.

    f (x) = 8x - 24

    f(x) decreasing when f (x) < 0 so 8x - 24 < 0

    8x < 24

    x < 3

    f(x) increasing when f (x) > 0 so 8x - 24 > 0

    8x > 24

    x > 3

    Check: f (2) = 8 X2 24 = -8

    Check: f (4) = 8 X4 - 24 = 8

    Increasing & Decreasing Functionsand Stationary Points

    Higher Outcome 3

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    Example 30

    Determine the intervals when the function

    f(x) = 2x3

    + 3x2

    - 36x + 41is (a) Stationary (b) Increasing (c) Decreasing.

    f (x) = 6x2+ 6x - 36

    = 6(x2+ x - 6)

    = 6(x + 3)(x - 2)

    Function is stationarywhen f (x) = 0

    ie 6(x + 3)(x - 2) = 0

    ie x = -3 or x = 2

    Increasing & Decreasing Functionsand Stationary Points

    Higher Outcome 3

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    www.mathsrevision.com We now use a special table of factors to

    determine when f (x) is positive & negative.

    x -3 2

    f(x) + 0 - 0 +

    Function increasingwhen f (x) > 0 ie x < -3 or x > 2

    Function decreasingwhen f (x) < 0 ie -3 < x < 2

    Increasing & Decreasing Functionsand Stationary Points

    Higher Outcome 3

    St ti P i ts

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    Stationary Pointsand Their Nature

    Consider this graph of y = f(x) again

    X

    y = f(x)

    a b c+

    +

    +

    +

    +

    -

    -

    0

    0

    0

    Higher Outcome 3

    St ti P i t

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    www.mathsrevision.com This curve y = f(x) has three types of stationary point.

    When x = a we have a maximum turning point (max TP)

    When x = b we have a minimum turning point (min TP)

    When x = c we have a point of inflexion (PI)

    Each type of stationary point is determined by thegradient ( f(x) ) at either side of the stationary value.

    Stationary Pointsand Their Nature

    Higher Outcome 3

    St ti P i t

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    Maximum Turning point

    x a

    f(x) + 0 -

    Minimum Turning Point

    x bf(x) - 0 +

    Stationary Pointsand Their Nature

    Higher Outcome 3

    St ti P i t

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    www.mathsrevision.com Rising Point

    of Inflection

    x cf(x) + 0 +

    Falling Pointof Inflection

    x df(x) - 0 -

    Stationary Pointsand Their Nature

    Higher Outcome 3

    St ti P i t

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    Example 31

    Find the co-ordinates of the stationary point on thecurve y = 4x3+ 1 and determine its nature.

    SP occurs when dy/dx = 0

    so 12x2= 0

    x2= 0

    x = 0

    Using y = 4x3+ 1

    if x = 0 then y = 1

    SP is at (0,1)

    Stationary Pointsand Their Nature

    Higher Outcome 3

    St ti P i ts

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    .com Nature Table

    x 0

    dy/dx + 0 +

    So (0,1) is a rising point of inflexion.

    Stationary Pointsand Their Nature

    dy/dx = 12x2

    Higher Outcome 3

    St ti n P ints

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    Example 32

    Find the co-ordinates of the stationary points on thecurve y = 3x4- 16x3 + 24 and determine their nature.

    SP occurs when dy/dx = 0

    So 12x3- 48x2 = 0

    12x2(x - 4) = 0

    12x2 = 0 or (x - 4) = 0

    x = 0 or x = 4

    Using y = 3x4- 16x3 + 24

    if x = 0 then y = 24

    if x = 4 then y = -232

    SPs at (0,24) & (4,-232)

    Stationary Pointsand Their Nature

    Higher Outcome 3

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    Stationary Points

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    Nature Table

    x 0

    dy/dx

    -2 2

    - 0 + 0 - 0 +

    So (-2,-6) and (2,-6) are Minimum Turning Points

    and (0,2) is a Maximum Turning Points

    Stationary Pointsand Their Nature

    Higher Outcome 3

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    Curve Sketching

    Note: A sketch is a rough drawing which includesimportant details. It is not an accurate scale drawing.

    Process

    (a) Find where the curve cuts the co-ordinate axes.

    for Y-axis put x = 0

    for X-axis put y = 0 then solve.

    (b) Find the stationary points & determine theirnature as done in previous section.

    (c) Check what happens as x +/- .

    This comes automatically if (a) & (b) are correct.

    Higher Outcome 3

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    Example 34

    Sketch the graph of y = -3x2+ 12x + 15

    (a) Axes If x = 0 then y = 15

    If y = 0 then -3x2+ 12x + 15 = 0 ( -3)

    x2- 4x - 5 = 0

    (x + 1)(x - 5) = 0

    x = -1 or x = 5

    Graph cuts axes at (0,15) , (-1,0) and (5,0)

    Curve SketchingHigher

    Outcome 3

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    using y = -3x2

    as x + then y -

    as x - then y -

    Sketching

    X

    Y

    y = -3x2+ 12x + 15

    Curve Sketching

    Cuts x-axis at -1 and 5

    Summarising

    Cuts y-axis at 15-15

    Max TP (2,27)(2,27)

    15

    Higher

    Outcome 3

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    Example 35Sketch the graph of y = -2x2(x - 4)(a) Axes

    If x = 0 then y = 0 X -4 = 0

    If y = 0 then -2x2(x - 4) = 0

    x = 0 or x = 4

    Graph cuts axes at (0,0) and (4,0) .

    -2x2= 0 or (x - 4) = 0

    (b) SPsy = -2x2(x - 4) = -2x3+ 8x2

    SPs occur where dy/dx = 0

    so -6x2+ 16x = 0

    Curve SketchingHigher

    Outcome 3

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    -2x(3x - 8) = 0

    -2x = 0 or (3x - 8) = 0

    x = 0 or x = 8/3

    If x = 0 then y = 0 (see part (a) )If x = 8/3 then y = -2 X(8/3)2 X(8/3 -4) =512/27nature

    x 0 8/3

    dy/dx - 0 + 0 -

    Curve SketchingHigher

    Outcome 3

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    Summarising(c) Large valuesusing y = -2x3 as x + then y -

    as x - then y +

    Sketch

    X

    y = -2x2(x 4)

    Curve Sketching

    Cuts x axis at 0 and 40 4

    Max TPs at (8/3, 512/27)(8/3, 512/27)

    Y

    Higher

    Outcome 3

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    Example 36 Sketch the graph of y = 8 + 2x2- x4

    (a) Axes If x = 0 then y = 8 (0,8)

    If y = 0 then 8 + 2x2- x4= 0

    Graph cuts axes at (0,8) , (-2,0) and (2,0)

    Let u = x2 so u2= x4

    Equation is now 8 + 2u - u2= 0

    (4 - u)(2 + u) = 0

    (4 - x2)(2 + x2) = 0

    or (2 + x) (2 - x)(2 + x2) = 0

    So x = -2 or x = 2 but x2 -2

    Curve SketchingHigher

    Outcome 3

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    (b) SPs SPs occur where dy/dx = 0

    So 4x - 4x3 = 0

    4x(1 - x2

    ) = 04x(1 - x)(1 + x) = 0

    x = 0 or x =1 or x = -1

    Using y = 8 + 2x2- x4

    when x = 0 then y = 8

    when x = -1 then y = 8 + 2 - 1 = 9 (-1,9)

    when x = 1 then y = 8 + 2 - 1 = 9 (1,9)

    Curve SketchingHigher

    Outcome 3

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    x -1 0 1

    dy/dx + 0 - 0 + 0 -

    So (0,8) is a min TP while (-1,9) & (1,9) are max TPs .

    Curve SketchingHigher

    Outcome 3

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    Max & Min on Closed Intervals

    In the previous section on curve sketching we dealtwith the entire graph.

    In this section we shall concentrate on the importantdetails to be found in a small section of graph.

    Suppose we consider any graph between the pointswhere x = a and x = b (i.e. a x b)

    then the following graphs illustrate where we wouldexpect to find the maximum & minimum values.

    Higher

    Outcome 3

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    y =f(x)

    Xa b

    (a, f(a))

    (b, f(b)) max = f(b) end point

    min = f(a) end point

    Max & Min on Closed Intervals

    Higher

    Outcome 3

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    x

    y =f(x)(b, f(b))

    (a, f(a))

    max = f(c ) max TP

    min = f(a) end point

    a b

    (c, f(c))

    c NB: a < c < b

    Max & Min on Closed Intervals

    Higher

    Outcome 3

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    From the previous three diagrams we should be able tosee that the maximum and minimum values of f(x) onthe closed interval a x b can be found either at

    the end points or at a stationary point between thetwo end points

    Example 37

    Find the max & min values of y = 2x3- 9x2 in the

    interval where -1 x 2.

    End points If x = -1 then y = -2 - 9 = -11

    If x = 2 then y = 16 - 36 = -20

    Max & Min on Closed Intervals

    Higher

    Outcome 3

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    Stationary points

    dy/dx = 6x2- 18x = 6x(x - 3)

    SPs occur where dy/dx = 0

    6x(x - 3) = 0

    6x = 0 or x - 3 = 0

    x = 0 or x = 3

    in interval not in interval

    If x = 0 then y = 0 - 0 = 0

    Hence for -1 x 2 , max = 0 & min = -20

    Max & Min on Closed Intervals

    Higher

    Outcome 3

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    Using function notation we can say that

    Domain = {xR: -1 x 2 }

    Range = {yR: -20 y 0 }

    Max & Min on Closed Intervals

    Higher

    Outcome 3

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    Optimization

    Note: Optimum basically means the best possible.

    In commerce or industry production costs and profitscan often be given by a mathematical formula.

    Optimum profit is as high as possible so we would look

    for a max value or max TP.

    Optimum production cost is as low as possible so wewould look for a min value or min TP.

    Higher

    Outcome 3

    Q. What is the maximum volume

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    Higher

    Outcome 3Example 41

    OptimizationQ. What is the maximum volume

    We can have for the givendimensions

    A rectangular sheet of foil measuring 16cm X10 cm hasfour small squares cut from each corner.

    16cm

    10cmx cm

    NB: x > 0 but 2x < 10 or x < 5

    ie 0 < x < 5

    This gives us a particular interval to consider !

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    hsrevision

    .com Considering the interval 0 < x < 5End Points

    V(0) = 0 X16 X10 = 0

    V(5) = 5X 6 X0 = 0

    SPs V '(x) = 12x2- 104x + 160

    = 4(3x2- 26x + 40)

    = 4(3x - 20)(x - 2)

    OptimizationHigher

    Outcome 3

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    .com SPs occur when V '(x) = 0

    ie 4(3x - 20)(x - 2) = 0

    3x - 20 = 0 or x - 2 = 0

    ie x = 20/3 or x = 2

    not in intervalin interval

    When x = 2 then V(2) = 2 X12 X6 = 144

    We now check gradient near x = 2

    OptimizationHigher

    Outcome 3

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    End points S(2) = 1 1 = 0

    There is no upper limit but as x S(x) 0.

    SPs occur where S (x) = 0

    3 2

    8 2'( ) 0S x

    x x

    1 2

    2

    2 4( ) 2 4 S x x x

    x x

    1 2 2 3

    2 3

    2 8'( ) 2 4 2 8S x x x x x

    x x

    OptimizationHigher

    Outcome 3

    O

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    8x2

    = 2x3

    8x2- 2x3 = 0

    2x2(4 x) = 0

    x = 0 or x = 4

    Out with interval In interval

    We now check the gradients either side of 4

    3 2

    8 2'( ) 0S x

    x xrearrange

    OptimizationHigher

    Outcome 3

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    Differentiation

    Higher Mathematics

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    Next

    Calculus

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    Differentiate24 3 7x x

    8 3x

    Calculus

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    Differentiate

    3 26 3 9x x x

    x

    3 26 3 9x x x

    x x x x

    2 16 3 9x x x

    Split up

    Straight line form

    22 6 9x x Differentiate

    Calculus

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    Differentiate

    3 1

    2 2

    2 5x x

    1 3

    2 23 1

    2 22 5x x

    1 3

    2 25

    23x x

    Calculus

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    Differentiate2

    3 1x

    x

    1 1

    2 23 2 1x x

    Straight line form

    Differentiate

    1 3

    2 21

    2

    32

    2x x

    1 3

    2 23

    2x x

    Calculus

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    Differentiate (3 5)( 2)x x

    23 6 5 10x x x Multiply out

    Differentiate 6 1x

    23 10x x

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    Calculus

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    Differentiate2( 2 )x x x

    multiply out3 22x x

    differentiate23 4x x

    Calculus

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    Differentiate

    3

    1 1

    x x

    1 3x x Straight line form

    Differentiate2 4( 3)x x

    2 43x x

    Calculus

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    Differentiate

    2x x x

    1

    22x x xStraight line form

    multiply out

    Differentiate

    5 3

    2 2x x

    3 1

    2 25 3

    2 2x x

    Calculus

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    Differentiate 2 4x x

    multiply out

    Simplify

    4 8 2x x x

    Differentiate

    6 8x x

    Straight line form

    1

    26 8x x 1

    23 1x

    Calculus

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    Differentiate5( 2)x

    Chain rule45( 2) 1x

    45( 2)xSimplify

    Calculus

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    Differentiate3(5 1)x

    Chain Rule23(5 1) 5x

    2

    15(5 1)xSimplify

    Calculus

    R i i

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    Differentiate2 4(5 3 2)x x

    Chain Rule 2 34(5 3 2) 10 3x x x

    Calculus

    R i i

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    Differentiate

    5

    2(7 1)x

    Chain Rule

    Simplify

    3

    25

    2(7 1) 7x

    3235

    2 (7 1)x

    Calculus

    R i i

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    Differentiate

    1

    2(2 5)x

    Chain Rule

    Simplify

    3

    21

    2(2 5) 2x

    3

    2(2 5)x

    Calculus

    R i i

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    Differentiate 3 1x

    Chain Rule

    Simplify

    Straight line form 1

    23 1x

    1

    21

    2 3 1 3x

    1

    23

    2 3 1x

    Calculus

    R i i

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    Differentiate

    4

    2

    5

    3x

    Chain Rule

    Simplify

    Straight line form2 45( 3)x

    2 520( 3) 2x x

    2 540 ( 3)x x

    Calculus

    R i i

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    Differentiate1

    2 1x

    Chain Rule

    Simplify

    Straight line form

    1

    2(2 1)x

    3

    21

    2(2 1) 2x

    3

    2

    (2 1)x

    Calculus

    R i i

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    Differentiate2

    2 cos sin3

    x x

    22sin cos

    3

    x x

    Calculus

    Revision

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    Differentiate 3cosx

    3sinx

    Calculus

    Revision

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    Differentiate cos 4 2sin 2x x

    4sin 4 4 cos 2x x

    Calculus

    Revision

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    Differentiate4cos x

    34cos sinx x

    Calculus

    Revision

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    Differentiate sinx

    Chain Rule

    Simplify

    Straight line form

    1

    2(sin )x

    1

    21

    2(sin ) cosx x

    1

    21

    2 cos (sin )x x

    1

    2

    cos

    sin

    x

    x

    Calculus

    Revision

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    Differentiate sin(3 2 )x

    Chain Rule

    Simplify

    cos(3 2 ) ( 2)x

    2cos(3 2 )x

    Calculus

    Revision

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    Differentiatecos5

    2

    x

    Chain Rule

    Simplify

    1

    2cos5xStraight line form

    1

    2sin 5 5x

    5

    2sin5x

    Calculus

    Revision

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    Differentiate ( ) cos(2 ) 3sin(4 )f x x x

    ( ) 2 sin(2 ) 12 cos(4 )f x x x

    Calculus

    Revision

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    Differentiate2 43200( )A x x

    x

    Chain Rule

    Simplify

    Straight line form2 1( ) 43200A x x x

    2( ) 2 43200A x x x

    2

    43200( ) 2A x x

    x

    Calculus

    Revision

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    Differentiate 22

    ( )f x x

    x

    Differentiate

    Straight line form

    1

    22( ) 2f x x x

    1 321

    2( ) 4f x x x

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    Calculus

    Revision

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    Differentiate

    62siny x

    Chain Rule

    Simplify

    62 cos 1dy

    xdx

    62cosdy

    xdx

    Calculus

    Revision

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    Differentiate3

    (8 )

    4

    A a a

    multiply out

    Differentiate

    2364

    A a a

    36

    2A a

    Calculus

    Revision

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    Differentiate

    1

    3 2( ) (8 )f x x

    Chain Rule

    Simplify

    1

    3 221

    2( ) (8 ) ( 2 )f x x x

    1

    2 3 2( ) (8 )f x x x

    Calculus

    Revision

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    Differentiate16

    , 0y x x

    x

    Differentiate

    Straight line form

    1

    216y x x

    3

    21 8dy

    xdx

    Calculus

    Revision

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    Differentiate23 3 16( )

    2

    A x x

    x

    Straight line form

    Multiply out23 3 3 3 16( )

    2 2A x x

    x

    Differentiate

    2 13 3( ) 24 32

    A x x x

    2

    ( ) 3 3 24 3A x x x

    Calculus

    Revision

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    Differentiate 1

    2( ) 5 4f x x

    Chain Rule

    Simplify

    1

    21

    2( ) 5 4 5f x x

    1

    25

    2( ) 5 4f x x

    Calculus

    Revision

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    Differentiate216( ) 240

    3

    A x x x

    32( ) 240

    3A x x

    Calculus

    Revision

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    Differentiate 2( ) 3 (2 1)f x x x

    Multiply out

    Differentiate

    3 2( ) 6 3f x x x

    2( ) 18 6f x x x

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