So this is going to be equal to positive 1 1 2. So this first part right over here is positive 1 1 2. And now let's evaluate the integral from zero to one of cosine pi, I don't need that first parenthesis, of cosine of pi x dx. What is this equal to? Now, if we were just trying to find the antiderivative of cosine of x, it's pretty straightforward. We know that the derivative with respect to x of sine of x is equal to cosine of x. Cosine of x. But that's not what we have here.