What is the derivative of sin(x²+1)according to x?

1 Answer
Mar 12, 2017

2x*cos(x^2 +1)

Explanation:

Inside of our sin(x) function is another function "x^2 +1" so we have to use the chain rule.

The derivative of the inside function x^2 +1 is 2x
(x^2 becomes 2x^(2-1) according to the power rule, 1 becomes 0 as it is a constant)

Now applying the chain rule (leaving the inside function unchanged):

2x*d/dx(sin(x))

The derivative of sin(x) is cos(x), so we find

d/dx(sin(x^2+1)) =

2x*cos(x^2+1)