How do you differentiate f(x) =arccos(2x + 1) ?

1 Answer
Jun 13, 2017

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

Explanation:

Recall that, d/dt arc cos t=-1/sqrt(1-t^2).

Therefore, f(x)-arc cos(2x+1)

rArr f'(x)=-1/sqrt{1-(2x+1)^2}*d/dx(2x+1),...[because," The Chain Rule]."

rArr f'(x)=-2/sqrt(-4x^2-4x)=-1/sqrt(-x^2-x).