1. Transformation of Functions
College Algebra
Section 2.7

2. Three kinds of Transformations
Horizontal and Vertical Shifts
A function involving more than one transformation can be graphed by performing transformations in the following order:
Horizontal shifting
Stretching or shrinking
Reflecting
Vertical shifting
Stretching or Shrinking
Reflections

3. How to recognize a horizontal shift.
Basic function
Basic function
Transformed function
Transformed function
Recognize transformation
Recognize transformation
The inside part of the function
The inside part of the function
has been replaced by
has been replaced by

4. How to recognize a horizontal shift.
Basic function
Transformed function
Recognize transformation
The inside part of the function
has been replaced by

5. The effect of the transformation on the graph
Replacing x with x – number SHIFTS the basic graph number units to the right
Replacing x with x + number SHIFTS the basic graph number units to the left

6. The graph of
Is like the graph of
SHIFTED 2 units to the right

7. The graph of
Is like the graph of
SHIFTED 3 units to the left

8. How to recognize a vertical shift.
Basic function
Basic function
Transformed function
Transformed function
Recognize transformation
Recognize transformation
The inside part of the function
remains the same
The inside part of the function
remains the same
2 is THEN subtracted
15 is THEN subtracted
Original function
Original function

9. How to recognize a vertical shift.
Basic function
Transformed function
Recognize transformation
The inside part of the function
remains the same
3 is THEN added
Original function

10. The effect of the transformation on the graph
Replacing function with function – number SHIFTS the basic graph number units down
Replacing function with function + number SHIFTS the basic graph number units up

11. The graph of
Is like the graph of
SHIFTED 3 units up

12. The graph of
Is like the graph of
SHIFTED 2 units down

13. How to recognize a horizontal stretch or compression
Basic function
Basic function
Transformed function
Transformed function
Recognize transformation
Recognize transformation
The inside part of the function
The inside part of the function
Has been replaced with
Has been replaced with

14. How to recognize a horizontal stretch or compression
Basic function
Transformed function
Recognize transformation
The inside part of the function
Has been replaced with

15. The effect of the transformation on the graph
Replacing x with number*x
COMPRESSES
the basic graph horizontally if number is greater than 1.
Replacing x with number*x
STRETCHES
the basic graph horizontally if number is less than 1.

16. The graph of
Is like the graph of
Horizontally COMPRESSED 3 times

17. The graph of
Is like the graph of
Horizontally STRETCHED 3 times

18. How to recognize a vertical stretch or compression
Basic function
Basic function
Transformed function
Transformed function
Recognize transformation
Recognize transformation
The inside part of the function
remains the same
The inside part of the function
remains the same
2 is THEN multiplied
4 is THEN multiplied
Original function
Original function

19. The effect of the transformation on the graph
Replacing function with number* function
STRETCHES
the basic graph vertically if number is greater than 1
Replacing function with number*function
COMPRESSES
the basic graph vertically if number is less than 1.

20. The graph of
Is like the graph of
STRETCHED 3 times vertically

21. The graph of
Is like the graph of
COMPRESSED 2 times vertically

22. How to recognize a horizontal reflection.
Basic function
Basic function
Transformed function
Transformed function
Recognize transformation
Recognize transformation
The inside part of the function
The inside part of the function
has been replaced by
has been replaced by
The effect of the transformation on the graph
Replacing x with -x FLIPS the basic graph horizontally

23. The graph of
Is like the graph of
FLIPPED horizontally

24. How to recognize a vertical reflection.
Basic function
Transformed function
Recognize transformation
The inside part of the function remains the same
The function is then multiplied by -1
Original function
The effect of the transformation on the graph
Multiplying function by FLIPS the basic graph vertically

25. The graph of
Is like the graph of
FLIPPED vertically

26. g(x)
Write the equation of the given graph g(x). The original function was f(x) =x2
(a)
(b)
(c)
(d)

27. Example

28. Summary of Graph Transformations
Vertical Translation:
y = f(x) + k Shift graph of y = f (x) up k units.
y = f(x) – k Shift graph of y = f (x) down k units.
Horizontal Translation: y = f (x + h)
y = f (x + h) Shift graph of y = f (x) left h units.
y = f (x – h) Shift graph of y = f (x) right h units.
Reflection: y = –f (x) Reflect the graph of y = f (x) over the x axis.
Reflection: y = f (-x)
Reflect the graph of y = f(x) over the y axis.
Vertical Stretch and Shrink: y = Af (x)
A > 1: Stretch graph of y = f (x) vertically by multiplying each ordinate value by A.
0 < A < 1: Shrink graph of y = f (x) vertically by multiplying each ordinate value by A.
Horizontal Stretch and Shrink: y = Af (x)
A > 1: Shrink graph of y = f (x) horizontally by multiplying each ordinate value by 1/A.
0 < A < 1: Stretch graph of y = f (x) vertically by multiplying each ordinate value by 1/A.