Question

How do you use the chain rule to differentiate `y=(7-x)^4`?

Answer 1

`y' = -4(7 - x)^3`

Explanation:

Use `(u^n)' = n u^(n-1) u'`

Let `u = 7-x; " "u' = -1; " "n = 4`

`y' = 4 (7-x)^3 (-1)`

Simplify:

`y' = -4 (7-x)^3`