X2 t01 02 solving quadratics (2013)

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Solving Quadratics073 .. 2 xxge

Solving Quadratics073 .. 2 xxge

2193

22893

x

Solving Quadratics073 .. 2 xxge

2193

22893

x

2193 i

2193or

2193 ixix

Solving Quadratics073 .. 2 xxge

2193

22893

x

OR

0732 xx

2193 i

2193or

2193 ixix

by completing the square

Solving Quadratics073 .. 2 xxge

2193

22893

x

OR

0732 xx

2193 i

2193or

2193 ixix

04

1923 2

x

04

1923 2

2

ix

by completing the square

Solving Quadratics073 .. 2 xxge

2193

22893

x

OR

0732 xx

2193 i

2193or

2193 ixix

04

1923 2

x

04

1923 2

2

ix

0219

23

219

23

ixix

by completing the square

Solving Quadratics073 .. 2 xxge

2193

22893

x

OR

0732 xx

2193 i

2193or

2193 ixix

04

1923 2

x

04

1923 2

2

ix

0219

23

219

23

ixix

ixix219

23or

219

23

by completing the square

Creating QuadraticsAll quadratics with real coefficients have

conjugate pairs as solutions

Creating QuadraticsAll quadratics with real coefficients have

conjugate pairs as solutions

2 ( )x z x z x z z x zz

Creating QuadraticsAll quadratics with real coefficients have

conjugate pairs as solutions

2 ( )x z x z x z z x zz

2 2Re( )x z x zz

Creating QuadraticsAll quadratics with real coefficients have

conjugate pairs as solutions

2 ( )x z x z x z z x zz

2 2Re( )x z x zz

-iiiii 4and4rootsith equation wquadratic theFind

Creating QuadraticsAll quadratics with real coefficients have

conjugate pairs as solutions

2 ( )x z x z x z z x zz

2 2Re( )x z x zz

8

-iiiii 4and4rootsith equation wquadratic theFind

17

Creating QuadraticsAll quadratics with real coefficients have

conjugate pairs as solutions

2 ( )x z x z x z z x zz

2 2Re( )x z x zz

8

0178 isequation 2 xx

-iiiii 4and4rootsith equation wquadratic theFind

17

Finding Square Rootsa ib x iy

Finding Square Rootsa ib x iy

2a ib x iy 2 22a abi b x iy

Finding Square Rootsa ib x iy

2a ib x iy 2 22a abi b x iy

ibaiyx If

yabxba

2then 22

Finding Square Rootsa ib x iy

2a ib x iy 2 22a abi b x iy

ibaiyx If

yabxba

2then 22

ie.g. 1612 Find

Finding Square Rootsa ib x iy

2a ib x iy 2 22a abi b x iy

ibaiyx If

yabxba

2then 22

ie.g. 1612 Find

1222 ba 162 ab

ab 8

Finding Square Rootsa ib x iy

2a ib x iy 2 22a abi b x iy

ibaiyx If

yabxba

2then 22

ie.g. 1612 Find

1222 ba 162 ab

ab 81264

22

aa

Finding Square Rootsa ib x iy

2a ib x iy 2 22a abi b x iy

ibaiyx If

yabxba

2then 22

ie.g. 1612 Find

1222 ba 162 ab

ab 81264

22

aa

06412 24 aa

Finding Square Rootsa ib x iy

2a ib x iy 2 22a abi b x iy

ibaiyx If

yabxba

2then 22

ie.g. 1612 Find

1222 ba 162 ab

ab 81264

22

aa

06412 24 aa 0164 22 aa

16or 4 22 aa

Finding Square Rootsa ib x iy

2a ib x iy 2 22a abi b x iy

ibaiyx If

yabxba

2then 22

ie.g. 1612 Find

1222 ba 162 ab

ab 81264

22

aa

06412 24 aa 0164 22 aa

16or 4 22 aa

42

ba solutionsreal no

Finding Square Rootsa ib x iy

2a ib x iy 2 22a abi b x iy

ibaiyx If

yabxba

2then 22

ie.g. 1612 Find

1222 ba 162 ab

ab 81264

22

aa

06412 24 aa 0164 22 aa

16or 4 22 aa

42

ba solutionsreal no ii 421612

ORa ib x iy

ORa ib x iy

2 2

2a b x

ab y

ORa ib x iy

2 2

2a b x

ab y

22 2 2 2 2 2

4 2 2 4 2 2

4 2 2 4

4

2 4 = 2

x y a b a b

a a b b a ba a b b

ORa ib x iy

2 2

2a b x

ab y

22 2 2 2 2 2

4 2 2 4 2 2

4 2 2 4

4

2 4 = 2

x y a b a b

a a b b a ba a b b

ibaiyx If2 2

2 2 2 2

then a b x

a b x y

ORa ib x iy

2 2

2a b x

ab y

22 2 2 2 2 2

4 2 2 4 2 2

4 2 2 4

4

2 4 = 2

x y a b a b

a a b b a ba a b b

ibaiyx If2 2

2 2 2 2

then a b x

a b x y

Note: y > 0, then a and b have same signy < 0, then a and b have different sign

ORa ib x iy

2 2

2a b x

ab y

22 2 2 2 2 2

4 2 2 4 2 2

4 2 2 4

4

2 4 = 2

x y a b a b

a a b b a ba a b b

ibaiyx If2 2

2 2 2 2

then a b x

a b x y

ie.g. 1612 Find

Note: y > 0, then a and b have same signy < 0, then a and b have different sign

ORa ib x iy

2 2

2a b x

ab y

22 2 2 2 2 2

4 2 2 4 2 2

4 2 2 4

4

2 4 = 2

x y a b a b

a a b b a ba a b b

ibaiyx If2 2

2 2 2 2

then a b x

a b x y

ie.g. 1612 Find 2 2

2 2

1220

a ba b

Note: y > 0, then a and b have same signy < 0, then a and b have different sign

ORa ib x iy

2 2

2a b x

ab y

22 2 2 2 2 2

4 2 2 4 2 2

4 2 2 4

4

2 4 = 2

x y a b a b

a a b b a ba a b b

ibaiyx If2 2

2 2 2 2

then a b x

a b x y

ie.g. 1612 Find 2 2

2 2

1220

a ba b

2

2

2 8 4 2

aaa

Note: y > 0, then a and b have same signy < 0, then a and b have different sign

ORa ib x iy

2 2

2a b x

ab y

22 2 2 2 2 2

4 2 2 4 2 2

4 2 2 4

4

2 4 = 2

x y a b a b

a a b b a ba a b b

ibaiyx If2 2

2 2 2 2

then a b x

a b x y

ie.g. 1612 Find 2 2

2 2

1220

a ba b

2

2

2 8 4 2

aaa

4b

Note: y > 0, then a and b have same signy < 0, then a and b have different sign

ORa ib x iy

2 2

2a b x

ab y

22 2 2 2 2 2

4 2 2 4 2 2

4 2 2 4

4

2 4 = 2

x y a b a b

a a b b a ba a b b

ibaiyx If2 2

2 2 2 2

then a b x

a b x y

ie.g. 1612 Find 2 2

2 2

1220

a ba b

2

2

2 8 4 2

aaa

4b

Note: y > 0, then a and b have same signy < 0, then a and b have different sign

ii 421612

( ) Find 5 4ii i

( ) Find 5 4ii i

2 2

2 2

5

41

a b

a b

( ) Find 5 4ii i

2 2

2 2

5

41

a b

a b

2

2

2 5 411 5 412

5 41 2

1 10 2 412

a

a

a

a

( ) Find 5 4ii i

2 2

2 2

5

41

a b

a b

2

2

2 5 411 5 412

5 41 2

1 10 2 412

a

a

a

a

2 1 5 41 521 5 412

5 41 2

1 10 2 412

b

b

b

( ) Find 5 4ii i

2 2

2 2

5

41

a b

a b

2

2

2 5 411 5 412

5 41 2

1 10 2 412

a

a

a

a

2 1 5 41 521 5 412

5 41 2

1 10 2 412

b

b

b

15 4 10 2 41 10 2 412

i i

2( ) Solve (2 ) (2 2 ) 0iii z i z i

2( ) Solve (2 ) (2 2 ) 0iii z i z i

22 2 4 2 22

2 4 4 1 8 82

2 5 122

i i iz

i i i

i i

2( ) Solve (2 ) (2 2 ) 0iii z i z i

22 2 4 2 22

2 4 4 1 8 82

2 5 122

i i iz

i i i

i i

5 12i 2 2

2 2

513

a ba b

2

2

2 8 4 2

aaa

3b

2( ) Solve (2 ) (2 2 ) 0iii z i z i

22 2 4 2 22

2 4 4 1 8 82

2 5 122

i i iz

i i i

i i

5 12i 2 2

2 2

513

a ba b

2

2

2 8 4 2

aaa

3b

2 2 32

i i

2( ) Solve (2 ) (2 2 ) 0iii z i z i

22 2 4 2 22

2 4 4 1 8 82

2 5 122

i i iz

i i i

i i

5 12i 2 2

2 2

513

a ba b

2

2

2 8 4 2

aaa

3b

2 2 32

i i

2 4 4 or 2 2 or 2 2

i i

i i

Cambridge: Exercise 1B; 1 to 4 ace etc, 5, 6, 7 cf,9, 10, 16 ac