# Thread: how to find the first derivative for this function?

1. ## how to find the first derivative for this function?

y(x)=[9x-3(1-6x^7)^2]^4

also this question

(3x^6/x^2-5)^-2

2. The first one is probably easiest to do by expanding the square and simplifying everything in the square brackets, before applying the chain rule.

What ideas do you have for the second?

3. Chain rule, chain rule, chain rule.

y'(x)=4*[[9x-3(1-6x^7)^2]^3][9 -6(1-6x^7)][-42x^6]

You just have to wade through it.

4. thanks