Evaluate the integral of sin x/2 dx. I know this should be easy, but my answer isn't the same as the answer key. is the answer really -2cosx/2 + C?

Question

anonymous · Answer

is that sin (x/2) or (sin x) / 2

anonymous · Answer

the answer you provided is correct if the question is

$$\int\limits_{}^{} \sin \frac{ x }{ 2 } dx$$

anonymous · Answer

oh, could you explain to me where the -2 in front of cos comes from? I was sort of confused by that.

anonymous · Answer

the negative part, or the 2?    the negative comes from the fact that integration of sin = - cos

the 2 comes from the substitution u = x/2, du = 1/2 dx, and so dx = 2 du