Posted by **Chris** on Sunday, September 20, 2009 at 5:24pm.

I'm trying to describe how the graph is related to the parent function.

The parent function is x^3

and the problem is:

y=-(0.8x)^3

I know its a reflection over the x-axis, but what is the formula for how much it expands or shrinks?

Like on another problem it's

y=|x|

and y= |0.2x|

The answer is that it expands by 5, but I'm not exactly sure how to get it.

Thanks.

- pre-calculus -
**MathMate**, Sunday, September 20, 2009 at 5:37pm
-(0.8x)^3 is stretching in the x-axis by a factor of (1/0.8) and as you noted, a reflection about the x-axis.

When ever the function f(x) is mapped to another by f(kx), it is stretching or contracting by a factor of (1/k). (1/k)>1 is a stretching, and (1/k)<1 is contracting.

- pre-calculus -more -
**MathMate**, Sunday, September 20, 2009 at 5:39pm
The stretching factor (1/k) applies to the x-direction only.

## Answer This Question

## Related Questions

- Pre-Calculus - Hello! I need help with these 2 questions: 1.) Describe how the ...
- Math - What is the parent function of h(x) = -x^2? Is it h(x) = x^2 or h(x) = -x...
- Pre-Calc - 1.) Describe how the graphs of f(x) = |2x| and g(x) = -|2x| are ...
- precalculus - State the parent function that must be transformed to create the ...
- Precalculus - Can someone help me with this question? I got the transformation ...
- Adv. Math. - Describe how the graph of y= abs(x-2) is related to the parent ...
- Pre-Calc - 1.) If you use the parent graph y=sqaureroot of x as a reference, how...
- Integrated Math 1 - A parent function generates a family of functions that are ...
- please help! :( math! - A parent function generates a family of functions that ...
- precalculus - is solving this possible graph each function with its parent graph...

More Related Questions