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Higher Unit 1
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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
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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
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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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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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www.math
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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)
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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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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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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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www.mathsrevision
.com (c) Large values
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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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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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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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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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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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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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
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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
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Differentiate
5
2(7 1)x
Chain Rule
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3
25
2(7 1) 7x
3235
2 (7 1)x
Calculus
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2(2 5)x
Chain Rule
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3
21
2(2 5) 2x
3
2(2 5)x
Calculus
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Differentiate 3 1x
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Straight line form 1
23 1x
1
21
2 3 1 3x
1
23
2 3 1x
Calculus
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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
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Differentiate1
2 1x
Chain Rule
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Straight line form
1
2(2 1)x
3
21
2(2 1) 2x
3
2
(2 1)x
Calculus
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Differentiate2
2 cos sin3
x x
22sin cos
3
x x
Calculus
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Differentiate 3cosx
3sinx
Calculus
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Differentiate cos 4 2sin 2x x
4sin 4 4 cos 2x x
Calculus
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Differentiate4cos x
34cos sinx x
Calculus
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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
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Differentiate sin(3 2 )x
Chain Rule
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cos(3 2 ) ( 2)x
2cos(3 2 )x
Calculus
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Differentiatecos5
2
x
Chain Rule
Simplify
1
2cos5xStraight line form
1
2sin 5 5x
5
2sin5x
Calculus
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Differentiate ( ) cos(2 ) 3sin(4 )f x x x
( ) 2 sin(2 ) 12 cos(4 )f x x x
Calculus
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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
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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
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Differentiate
62siny x
Chain Rule
Simplify
62 cos 1dy
xdx
62cosdy
xdx
Calculus
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Differentiate3
(8 )
4
A a a
multiply out
Differentiate
2364
A a a
36
2A a
Calculus
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Differentiate
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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
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Differentiate16
, 0y x x
x
Differentiate
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1
216y x x
3
21 8dy
xdx
Calculus
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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
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Differentiate 1
2( ) 5 4f x x
Chain Rule
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1
21
2( ) 5 4 5f x x
1
25
2( ) 5 4f x x
Calculus
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Differentiate216( ) 240
3
A x x x
32( ) 240
3A x x
Calculus
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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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