13.3 Transformations of graphs — Practise with help
Try each question before opening a hint. Move through the steps in order.
Warm-up: remember
- Find if .
- State the -intercept of .
- Give the image of after moving it two units up.
- Expand .
Answers
; ; ; .
Practise with help
1. Translate two units right.
Hint
For a right shift, replace with .
Next step
Substitute wherever the original rule has .
Full working
The new rule is .
2. Starting with , move the graph two units right and three units down.
Hint
Make the horizontal change inside the brackets and the vertical change outside.
Next step
First write , then subtract three.
Full working
. The turning point is .
3. Reflect in the -axis.
Hint
Change the sign of every output.
Next step
Write the new output as .
Full working
The reflected rule is .
4. A point lies on . Find its image under reflection in the -axis.
Hint
Keep the input fixed and change the sign of the output.
Next step
The new output is .
Full working
The image is , because the input stays fixed and the output changes sign.