We just have to figure out what the antiderivative of cosine of x is or what an antiderivative of cosine of x is evaluated at pi over 2. And from that, subtract it evaluated at 0. So what's the antiderivative of cosine of x? Or what's an antiderivative? Well, we know if we take the derivative, let me write this up here. We know that if we take the derivative of sine of x, we get cosine of x. So the antiderivative of cosine of x is sine of x.