What is the Chain Rule for Derivatives?

[thomasrules]

Given: $$h=f\circ g , g(2)=5, g\prime(2)=3$$, and $$f\prime(5)=-2$$
Determine $$h\prime(2)$$

 

[radou]

Use the fact that (f o g) ' (x) = f ' (g(x)) * g ' (x).

 

[thomasrules]

i don't get it

 

[radou]

It's right in front of you, think about it.

 

[dontdisturbmycircles]

The Chain rule states that given f(g(x)), the derivative f ' (g(x)) can be found by finding the derivative of f at g(x) multiplied by the derivative of g(x). Which is what radou pointed out.

Do we know f ' (g(x))? Think about what g(x) equals in this case. Do we know g ' (x)? Think! The chain rule is very important!

 

[thomasrules]

got it ty...