1. ## Differentiating a function

Hi, I'm getting a bit confused about a question and I was wondering if you could help me out with where to start.
I need to find the first and second derivative of;

f(x)=(2x3+2x2-5x-2)/(2(x2-1))

So what would f'(x) and f''(x) equal?

2. Originally Posted by Lilly
Hi, I'm getting a bit confused about a question and I was wondering if you could help me out with where to start.
I need to find the first and second derivative of;

f(x)=(2x3+2x2-5x-2)/(2(x2-1))

So what would f'(x) and f''(x) equal?
If f(x)=u/v there is a formula for f'(x) It is f'(x)=(vu'-uv')/v^2 To get f''(x) apply same formula again to f'(x)

3. will I need to apply the chain rule to v though?

4. Originally Posted by Lilly
will I need to apply the chain rule to v though?
Not necessarily. v = 2x^2 - 2 so v' is just 4x. You will have to do the chain rule to u, though.

5. Originally Posted by Lilly
will I need to apply the chain rule to v though?
v=2(x^2-1)=2x^2-2 So v'=4x

6. (af)'= af', for a a constant, is really more fundamental than the "chain rule".

And, by the way, a question about how to find a derivative has nothing to do with "differential equations".

7. ## Differentiating a function

This is the different function, I am confused with this question my math is not more strong. But I hope It will be good and more interesting also.

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