Question

if f(x)= cos 2x then f'x=?by
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Answer 1

Answer:

-2sin(2x)

Step-by-step explanation:

Derivative of cos(2x):

First, take 2x = y:

Derivative of cos(y): -(dy/dx)(sin(y))

dy/dx = d(2x)/dx = 2:

-2sin(y): -2sin(2x)

Therefore answer is -2sin(2x)

Hope it helps!