Question

Derivative of cos 2x frim first principle method

Answer 1

The derivative of cos(2x) is -2sin(2x). The process of finding this derivative uses the chain rule. We can use integrals to check our work when finding derivatives. If D(x) is the derivative of f(x), then the integral of D(x) is f(x) + C, where C is a constant.

Answer 2

Answer:

hi mate here is ur answer

y=cos(2x)

Let, t=2x

Implies, dt/dx=2.

Also, y=cos(t)

Implies, dy/dt= -sin(t) .

By Chain rule,

dy/dx=(dy/dt)×(dt/dx)

dy/dx=[-sin(t)]×2

dy/dx=-2sin(t)

hope it help!!!!!!!!!!!