The Student Room Group
Competition - post a photo you've taken of nature >>
Competition - post a photo you've taken of nature >>
Competition - post a photo you've taken of nature >>

AQA C3 extended chain rule - Differentiate y=2cos^5(4x)

I'm stuck on the following question 4:-

I don't know how to differentiate it using the extended chain rule when there is a 2 as a coefficient in front of it all
heres my working:

What do i do with the 2?
Reply 1
Avatar for davros
davros
16
Original post by Sayless
I'm stuck on the following question 4:-

I don't know how to differentiate it using the extended chain rule when there is a 2 as a coefficient in front of it all
heres my working:

What do i do with the 2?


The same thing you do with a "2" in front of any function!

The derivative of a function measures its gradient at a general point, so if the function is multiplied by 2 everywhere, then the gradient will be too.

Pretend the 2 isn't there, work out the derivative, then multiply by the 2 at the end :smile:
The two doesn't matter when it comes to differentiation, as it is a constant and not a variable.

eg.

dydx(2x)=2dydx(x) \frac{dy}{dx}(2x) = 2\frac{dy}{dx}(x)

Quick Reply

Related discussions

Latest

Trending

Trending

Articles for you