Question

whats the derivative of y=x-2cosx

Answer 1

Do you know the derivative of \(x\)? What about \(2\cos x\)?

Answer 2

You just need to distribute the differential. so it's the derivative of x, and the derivative of -2cos(x). the derivative of x is 1, and the derivative of -2cos(x) is 2sin(x)

Answer 3

final answer should be 1 + 2sin(x)

Answer 4

just remember that you are taking the derivative in respect to x because that is the only variable of the function

derivative of x is 1 and derivative of -2cos(x) is 2sin(x)

put it together and you have \[f \prime=1+2\cos(x)\]