How to find the derivative of 3arccos(x/2)? Calculus Differentiating Trigonometric Functions Differentiating Inverse Trigonometric Functions 1 Answer bp Apr 16, 2015 -3/[2sqrt(1-x^2/4)] Let y= 3 arc cosx/2, so that y/3 = arc cosx/2 Thus, cosy/3= x/2 and hence siny/3 = sqrt(1- x^2/4) Now differentiate, -1/3 siny/3 dy/dx = 1/2 dy/dx= -3/[2sin(y/3)] = -3/[2sqrt(1-x^2/4)] Answer link Related questions What is the derivative of f(x)=sin^-1(x) ? What is the derivative of f(x)=cos^-1(x) ? What is the derivative of f(x)=tan^-1(x) ? What is the derivative of f(x)=sec^-1(x) ? What is the derivative of f(x)=csc^-1(x) ? What is the derivative of f(x)=cot^-1(x) ? What is the derivative of f(x)=(cos^-1(x))/x ? What is the derivative of f(x)=tan^-1(e^x) ? What is the derivative of f(x)=cos^-1(x^3) ? What is the derivative of f(x)=ln(sin^-1(x)) ? See all questions in Differentiating Inverse Trigonometric Functions Impact of this question 2469 views around the world You can reuse this answer Creative Commons License