## mathcalculus Group Title HELP: Use your knowledge of the derivative to compute the limit given below: The derivative that is being calculated is 11 months ago 11 months ago

1. mathcalculus Group Title

2. mathcalculus Group Title

im confused. am i suppose to use the power rule or quotient rule to find the derivative?

3. asnaseer Group Title

do you know how to write the general form for the derivative of f(x)?

4. SithsAndGiggles Group Title

It sounds like the problem is asking you to recognize that the given limit is the definition of the derivative of some function. Given $$\displaystyle\lim_{h\to0}\dfrac{f(x+h)-f(x)}{h}$$, find $$f(x)$$. Then, simply compute the derivative.

5. asnaseer Group Title

^

6. mathcalculus Group Title

yes

7. mathcalculus Group Title

im not sure how to start this

8. SithsAndGiggles Group Title

Well do you know how to find the derivative? The way the question is stated makes it sound like you've learned some of or all the "rules" for differentiation. In this case, since $$f(x)=\dfrac{1}{x^6}$$, you would apply the power rule to find the derivative, and that would be your answer.

9. mathcalculus Group Title

right i used the power rule.

10. SithsAndGiggles Group Title

Okay, so that gives you $f(x)=\frac{1}{x^6}=x^{-6}~\Rightarrow~f'(x)=\cdots$

11. mathcalculus Group Title

-6/x^7

12. SithsAndGiggles Group Title

Right.

13. mathcalculus Group Title

^_^