# Thread: Need some function help.

1. ## Need some function help.

Hey guys,

I have a math assignment due on Monday, and I'm having difficulties understanding what two of the questions are asking.

1) Calulcate f(x+h) when:
a) f(x)=x^2
...
In each case, write down the corresponding expression for f(x+h) - f(x). Replace the right side of the equation with x+h for each instance.
My instructor didn't really go over questions like these all that much in class, so I'm not entirely sure what the question is asking. I have a similar issue with this question:

2) If f(x)=1/(1-x)^2, find f(x/t).
Is this just asking to find (1/(1-x)^2)/t?

Any help would be greatly appreciated!

2. Is this assignment for a grade?

3. Originally Posted by Eternalspirit
Is this just asking to find (1/(1-x)^2)/t?
If $\displaystyle f(x)=x^2$ then $\displaystyle f(x+h)=(x+h)^2=~?$ (EXPAND)

If $\displaystyle f(x)=\frac{1}{(1+x)^2}$ then $\displaystyle f\left(\frac{x}{t}\right)=\frac{1}{\left(1+\frac{x }{t}\right)^2}$

4. Originally Posted by Ackbeet
Is this assignment for a grade?
Yeah.. I'm not looking for an answer, just what the questions are asking in a clearer way.

5. Originally Posted by Plato
If $\displaystyle f(x)=x^2$ then $\displaystyle f(x+h)=(x+h)^2=~?$ (EXPAND)

If $\displaystyle f(x)=\frac{1}{(1+x)^2}$ then $\displaystyle f\left(\frac{x}{t}\right)=\frac{1}{\left(1+\frac{x }{t}\right)^2}$
For the first part.. I got that far as well, but what do I do about the second part of the question, asking for f(x+h)-f(x)?

Also, thanks for point 2! That's initially what I was leaning towards.

6. Can you expand and simplify $\displaystyle [(x+h)^2]-[(x^2)]~?$

7. Originally Posted by Plato
Can you expand and simplify $\displaystyle [(x+h)^2]-[(x^2)]~?$