How do you find the derivative of y=arcsin(2x+1)?

1 Answer
Sep 19, 2016

dy/dx=1/sqrt(-x^2-x)

Explanation:

Note that:

d/dxarcsin(x)=1/sqrt(1-x^2)

So, according to the chain rule:

d/dxarcsin(f(x))=(f'(x))/sqrt(1-f(x)^2)

So, where f(x)=2x+1, and f'(x)=2:

dy/dx=d/dxarcsin(2x+1)=2/sqrt(1-(2x+1)^2)

=2/sqrt(1-(4x^2+4x+1))

=2/sqrt(-4x^2-4x)

=2/(sqrt4sqrt(-x^2-x))

=1/sqrt(-x^2-x)