Vertical shifts (up) A familiar example: Vertical shift up 3: y-values each increase by 3 graph is...

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Vertical shifts (up) x -5 -4 -3 -2 -1 0 1 2 3 4 5 y 25 16 9 4 1 0 1 4 9 16 25 A familiar example: 2 gx x x -5 -4 -3 -2 -1 0 1 2 3 4 5 y 28 19 12 7 4 3 4 7 12 19 28 Vertical shift up 3: 2 3 f x x y-values each increase by 3 graph is shifted up 3 units -10 -5 0 5 10 15 20 -8 -6 -4 -2 0 2 4 6 8 2 gx x -10 -5 0 5 10 15 20 -8 -6 -4 -2 0 2 4 6 8 2 3 f x x

Transcript of Vertical shifts (up) A familiar example: Vertical shift up 3: y-values each increase by 3 graph is...

Page 1: Vertical shifts (up) A familiar example: Vertical shift up 3: y-values each increase by 3 graph is shifted up 3 units.

Vertical shifts (up)

x -5 -4 -3 -2 -1 0 1 2 3 4 5

y 25 16 9 4 1 0 1 4 9 16 25

A familiar example: 2g x x

x -5 -4 -3 -2 -1 0 1 2 3 4 5

y 28 19 12 7 4 3 4 7 12 19 28

Vertical shift up 3: 2 3f x x

y-values each increase by 3

graph is shifted up 3 units-10

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-8 -6 -4 -2 0 2 4 6 8

2g x x

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2 3f x x

Page 2: Vertical shifts (up) A familiar example: Vertical shift up 3: y-values each increase by 3 graph is shifted up 3 units.

x -5 -4 -3 -2 -1 0 1 2 3 4 5

y 20 11 4 -1 -4 -5 -4 -1 4 11 20

2 5f x x Vertical shift down 5:

y-values each decrease by 5

x -5 -4 -3 -2 -1 0 1 2 3 4 5

y 25 16 9 4 1 0 1 4 9 16 25

Original curve: 2g x x

graph is shifted down 5 units

More vertical shifts (down)

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2g x x

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2 5f x x

Page 3: Vertical shifts (up) A familiar example: Vertical shift up 3: y-values each increase by 3 graph is shifted up 3 units.

Horizontal shifts (right)

x -5 -4 -3 -2 -1 0 1 2 3 4 5

y 64 49 36 25 16 9 4 1 0 1 4

x -5 -4 -3 -2 -1 0 1 2 3 4 5

y 25 16 9 4 1 0 1 4 9 16 25

Original curve: 2g x x

23f x x Horizontal shift right 3:

y-values are shifted to the right 3 units

graph is shifted right 3 units-10

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-8 -6 -4 -2 0 2 4 6 8

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2g x x 2

3f x x

Page 4: Vertical shifts (up) A familiar example: Vertical shift up 3: y-values each increase by 3 graph is shifted up 3 units.

x -5 -4 -3 -2 -1 0 1 2 3 4 5

y 1 0 1 4 9 16 25 36 49 64 81

x -5 -4 -3 -2 -1 0 1 2 3 4 5

y 25 16 9 4 1 0 1 4 9 16 25

Original curve: 2g x x

More horizontal shifts (left)

24f x x Horizontal shift Left 4:

y-values are shifted to the left 4 units

graph is shifted left 4 units-10

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-8 -6 -4 -2 0 2 4 6 8

2g x x

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-8 -6 -4 -2 0 2 4 6 8

24f x x

Page 5: Vertical shifts (up) A familiar example: Vertical shift up 3: y-values each increase by 3 graph is shifted up 3 units.

Summary of vertical and horizontal shifts

f x g x k

Given a function g whose graph is known, and a positive

number k, the graph of the function f is:

graph of g, shifted up k units

f x g x k

f x g x k

f x g x k

graph of g, shifted down k units

graph of g, shifted right k units

graph of g, shifted left k units

CAUTION:the signs here may be counter-intuituve!

Page 6: Vertical shifts (up) A familiar example: Vertical shift up 3: y-values each increase by 3 graph is shifted up 3 units.

Reflections about the x-axis

x -5 -4 -3 -2 -1 0 1 2 3 4 5

y und und und und und 0.0 1.0 1.4 1.7 2.0 2.2

x -5 -4 -3 -2 -1 0 1 2 3 4 5

y und und und und und 0.0 -1.0 -1.4 -1.7 -2.0 -2.2

undefined if x < 0

Original curve:

Reflected about x-axis: f x x

-1.0

0.0

1.0

2.0

3.0

4.0

-6 -4 -2 0 2 4 6

-4.0

-3.0

-2.0

-1.0

0.0

1.0

-6 -4 -2 0 2 4 6

g x x

g x x

f x x

y-values each replaced by their opposite

Page 7: Vertical shifts (up) A familiar example: Vertical shift up 3: y-values each increase by 3 graph is shifted up 3 units.

x -5 -4 -3 -2 -1 0 1 2 3 4 5

y 2.2 2.0 1.7 1.4 1.0 0.0 und und und und und

undefined if x > 0

Reflections about the y-axis

x -5 -4 -3 -2 -1 0 1 2 3 4 5

y und und und und und 0.0 1.0 1.4 1.7 2.0 2.2

undefined if x < 0

Original curve:

Reflected about y-axis: f x x

-1.0

0.0

1.0

2.0

3.0

4.0

-6 -4 -2 0 2 4 6

g x x

-1.0

0.0

1.0

2.0

3.0

4.0

-6 -4 -2 0 2 4 6

g x x f x x

mirror image of y-values

domain: 0,

domain: ,0

Page 8: Vertical shifts (up) A familiar example: Vertical shift up 3: y-values each increase by 3 graph is shifted up 3 units.

Summary of reflections

f x g x

Given a function g whose graph is known, the graph of the

function f is:

graph of g, reflected about the x-axis

f x g x graph of g, reflected about the y-axis

domain of f is "opposite" of domain of g

i.e. if domain of g is [a,b] then domain of f is [-b,-a]

domain of f is domain of g

Page 9: Vertical shifts (up) A familiar example: Vertical shift up 3: y-values each increase by 3 graph is shifted up 3 units.

Vertical stretching

g x

A cubic polynomial:

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x -5 -4 -3 -2 -1 0 1 2 3 4 5y -20 -1.6 7.2 8.8 5.6 0 -5.6 -8.8 -7.2 1.6 20 2f x g x

g x

f x

each y-value doubles

x -5 -4 -3 -2 -1 0 1 2 3 4 5y -10 -0.8 3.6 4.4 2.8 0 -2.8 -4.4 -3.6 0.8 10

Page 10: Vertical shifts (up) A familiar example: Vertical shift up 3: y-values each increase by 3 graph is shifted up 3 units.

Vertical Shrinking

g x

The same cubic:

1

3f x g x

x -5 -4 -3 -2 -1 0 1 2 3 4 5y -3.3 -0.3 1.2 1.5 0.9 0 -0.9 -1.5 -1.2 0.3 3.3

x -5 -4 -3 -2 -1 0 1 2 3 4 5y -10 -0.8 3.6 4.4 2.8 0 -2.8 -4.4 -3.6 0.8 10

each y-value shrinks by 1/3

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g x

f x

Page 11: Vertical shifts (up) A familiar example: Vertical shift up 3: y-values each increase by 3 graph is shifted up 3 units.

Horizontal Stretching

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2f x g x

g x

The same cubic:

Y-values are stretched out from the centerx -5 -4 -3 -2 -1 0 1 2 3 4 5

y 4.4 4.4 3.8 2.8 1.5 0.0 -1.5 -2.8 -3.8 -4.4 -4.4

x -5 -4 -3 -2 -1 0 1 2 3 4 5y -10 -0.8 3.6 4.4 2.8 0 -2.8 -4.4 -3.6 0.8 10

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g x

f x

Page 12: Vertical shifts (up) A familiar example: Vertical shift up 3: y-values each increase by 3 graph is shifted up 3 units.

Horizontal shrinking

2f x g x

The same cubic

x -5 -4 -3 -2 -1 0 1 2 3 4 5y -10 -0.8 3.6 4.4 2.8 0 -2.8 -4.4 -3.6 0.8 10

x -5 -4 -3 -2 -1 0 1 2 3 4 5y -170 -78 -25 -0.8 4.4 0.0 -4.4 0.8 25 78 170

g x

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g x

f x

Page 13: Vertical shifts (up) A familiar example: Vertical shift up 3: y-values each increase by 3 graph is shifted up 3 units.

Summary of stretching and shrinking

f x cg x

Given a function g whose graph is known, and a positive

number c, the graph of the function f is:

graph of g, stretched vertically

f x g cx

graph of g, shrunk vertically

graph of g, shrunk horizontally

graph of g, stretched horizontally

1c

1c

1c

1c