What is the derivative of # (cos x)^2 - cos x#? Calculus Differentiating Trigonometric Functions Derivative Rules for y=cos(x) and y=tan(x) 1 Answer Ratnaker Mehta Jun 13, 2016 #sinx-sin2x.# Explanation: #d/dx[ cos^2x-cosx]=d/dx((cosx)^2)-d/dxcosx =2*(cosx)*d/dxcosx-(-sinx)=2cosx(-sinx)+sinx=sinx-2cosxsinx=sinx-sin2x.# Answer link Related questions What is the derivative of #y=cos(x)# ? What is the derivative of #y=tan(x)# ? How do you find the 108th derivative of #y=cos(x)# ? How do you find the derivative of #y=cos(x)# from first principle? How do you find the derivative of #y=cos(x^2)# ? How do you find the derivative of #y=e^x cos(x)# ? How do you find the derivative of #y=x^cos(x)#? How do you find the second derivative of #y=cos(x^2)# ? How do you find the 50th derivative of #y=cos(x)# ? How do you find the derivative of #y=cos(x^2)# ? See all questions in Derivative Rules for y=cos(x) and y=tan(x) Impact of this question 1357 views around the world You can reuse this answer Creative Commons License