10/5/22 - Horizontal Transformations Flashcards
Which coordinates do horizontal transformations change?
x-coordinates
How do you represent a horizontal reflection?
If f(x) is a function, then f(-x) is its horizontal reflection. The graph is reflected across the y-axis.
How do you represent a horizontal stretch?
f(Bx), where B is a constant
f(4x) is a horizontal stretch by ____
1/4
f(1/2 x) is a horizontal stretch by ____
2
How do you graph a horizontal stretch f(Bx)?
Pick points on f(x) and multiply the x-coordinates by 1/B
How do you represent a horizontal shift?
f(x - h)
If h is positive, it’s a shift to the right
If h is negative, it’s a shift to the left
Describe the horizontal shift in f(x - 3)
3 units to the right
Describe the horizontal shift in f(x + 8)
8 units to the left
How do you graph a horizontal shift f(x - h)?
Pick points on f(x) and add h to the x-coordinates
If you have the graph of f(x) how do you graph f(2x + 2)?
- Write it as f(2(x + 1)), B = 2, h = -1
- Do a vertical stretch by 1/B or 1/2. Multiply x-coordinates by 1/2.
- Do a vertical shift by h or -1. Subtract 1 from the x-coordinates. The graph is shifted 1 unit left.