1 Modeling Transformations 2D Transformations 3D Transformations OpenGL Transformation.
1. Transformations
description
Transcript of 1. Transformations
1. TransformationsTo graph: Identify parent function and adjust key points.Function To Graph: Move key point (x,y) to:
Vertical Shift upVertical Shift down
Horizontal Shift leftHorizontal Shift right
Reflection about x-axisReflection about y-axis
Vertical stretch if Vertical shrink if
Horizontal stretch if 0 < b <1Horizontal shrink if b > 1
cxfcxf
)()(
)()(
cxfcxf
),(),(),(),(
ycxyxycxyx
),(),(),(),(
cyxyxcyxyx
)()(
xfxf
),(),(),(),(
yxyxyxyx
)(xaf ),(),( ayxyx
),1(),( yxb
yx )(bxf
1a10 a
Warm-up.
452 2) x
1)( 1) 2
3
x
xxf
For each function below, a) state the domain b) even/odd/neither c) symmetry
Suppose
Warm-up.
xxxxf 4)( 23
1) If , what is x?
2) Find all intercepts of the graph of f
4)( xf
Suppose and are points on a line.
Write the equation of the line containing these 2 points.
Warm-up.
3)1( f 7)2( f
Warm-up.
1. Evaluate the following:
2. State the domain for this function
3. Sketch the graph
40 if 04 if 2
4 if 1
xx x
xxf
)0()1()4()5(
ffff
2.6 Function Transformations
2.6 Function Transformations
a. Vertical Shift
f (x) x 2 2Parent function :
Shift Down 2 units
2x
Vertical Shift (or translation) shifts UP k units
shifts DOWN k units
kxf )(
kxf )(
b. Horizontal Shift
f (x) (x 3)2
Parent function : 2x
Shift left 3 units
Horizontal shift (or translation) shifts LEFT h units
shifts RIGHT h units
)( hxf
)( hxf
2a. Reflection about the x-axis
f (x) xParent function : x
Reflect over x-axis.
Reflects graph about the x-axis)(xf
2b. Reflects graph about the y-axis
f (x) xParent function :
Reflect over y-axis.
x
Reflects graph about the y-axis)( xf
3a. Stretch (dilate) the graph vertically
f (x) 2 x
)(xaf
Parent function :
Stretch vertically by : 2
|| x
If a > 1, stretches graph vertically
If 0 < a < 1, compresses graph vertically
)(xaf
3b. Horizontal Stretch/Compress
f (x) 12
x
)(bxf
Horizontal Scale
If b > 1, compresses horizontally (x-values by 1/b)If 0 < b < 1, stretches horizontally (x-values by 1/b)
)(bxf
3b. Horizontal Dilation (Scale)
When scale is “inside” the parent function,it is preferable to pull it OUTSIDE the parent function and apply
vertical dilation
32)( xxf
Practice
4. Sequence of TransformationsWhen a function has multiple transformatinos applied, does
the order of the transformations matter?
23 xxf Which operation is first: Reflection or Shift ?
5. a) Rewrite function in standard form
Step 1: Always, factor out coefficients and write in standard form, before doing transformations!
khxbfaxf ))((
Rewrite in standard form:
23 xy
Perform the transformations in this order
khxbfa )(
1.Vertical scale Vertical shift
4.
Horizontal shift3.
Horizontal scale2.
6. Describe sequence of Transformations
23 xyStandard Form:Parent FunctionReflection over x-axisReflection over y-axisScale yScale xShift L/RShift U/D
6. Describe sequence of TransformationsStandard Form:Parent FunctionReflection over x-axisReflection over y-axisScale yScale xShift L/RShift U/D
22)( xxf
f (x) (x 1)3 2
6. Describe sequence of Transformations
Standard Form:Parent FunctionReflection over x-axisReflection over y-axisScale yScale xShift L/RShift U/D
For each function, describe (in order) the sequence of transformations and sketch the final graph.1) 4)
2) 5)
3)
6. More Practice…
3)1(2)( 2 xxf
2)()( 3 xxf
1|3|2)( xxf
1)2()( xxf
452)( xxf
7. Domain
How is the domain of a function affected by the transformations?
xxf )(
2)( xxf 1)( xxf xxf )(xxf )(
11. Write an equation from the graph
1. Identify parent (shape)
2. Compare key points to determine if y values are scaled.
3. Observe translations and reflections
4. Write in standard form khxbfaxf ))((
1. Library of Functions (Take note of key points)
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Linear Function( )f x mx b
2
Square Function
( )f x x 3
Cube Function
( )f x x
Square Root Function
( )f x x
3
Cube Root
( )f x x
Reciprocal1( )f xx
Absolute Value( )f x x
“Slope” = 1
Move:Right 1, Up 1
to next point on graph
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1
1
1
College Algebra Notes 2.6 Write the Function from the GraphFor each graph below:a)Name the parent function b) Describe the sequence of transformations (in order) c) Determine the function that describes the graph d) Verify key points by plugging into your function.
1) 2)
3) 4)
11. Write an equation from the graph
f (x) (x 2)3
f (x) x 2 3
f (x) x 1
f (x) 2 x 3 2
Transformations
f (x) 1
( x) 2
1)
2)
3)
Even or Odd ?
Warm-up.a) List the sequence of transformations and sketchb) List the transformations that are made to each key point of
the parent function.
452 2) x
6121)( 1)
2
xxg
1)( 3) 2
3
x
xxf
Method 2: Less Preferred method
When a function is not in the standard form, perform transformations in this order:
1) Horizontal shift2) Stretch/shrink3) Reflect4) Vertical stretch Shrink
8. A second method for sequence of transformations
Perform the transformations in this order
khxbfa )(
1.Vertical scale by a If a is negative, reflects across x-axis
Vertical shift+k: shift up k
-k : shift down k
4.
Horizontal shift-h : shift to right+h : shift to left
3.Horizontal scale by
If b is negative, reflects across y-axis
b/12.
yx
byx ,1,
ayxyx ,,