## Ackbar 3 years ago What is the product rule?

1. Owlfred

Hoot! You just asked your first question! Hang tight while I find people to answer it for you. You can thank people who give you good answers by clicking the 'Good Answer' button on the right!

2. LeoMessi

product rule is for finding the derivative of the product of two functions: $(f(x) * g(x))' = f(x) * g'(x) + g(x) * f'(x)$

3. fauxshaux

yes, and you can expand this concept to products of more than 2 functions...just remember to take the derivative of each product...so one derivative per term...

4. Ackbar

i'm sort of lost for the application to more than 2 functions... :/

5. fauxshaux

$(f(x) * g(x) * h(x))' = f(x) * h(x) *g'(x) + g(x) * h(x) * f'(x) + g(x) * f(x) *h'(x)$

6. Ackbar

oooh, i was having trouble visualizing that one. thanks

7. smbogle

I think by taking the change variation of the area as 2pi.r, we get what we are looking for by integrating.

8. TigerHound

$(uv)\prime = u \prime \times v +v \prime \times u$