So now we want to evaluate at x equals pi over four. So when that is equal to pi over four, pi over four. So let's see, this is going to be, this is going to be equal to sine of, what's three pi over two minus pi over four? I'll do that over here. So if you have a common denominator, that is six pi over four, the same thing as three pi over two, minus pi over four, sorry, minus pi over four is equal to five, five pi over four. So it's sine of five pi over four, five pi over four, over cosine squared of five pi over four, and then times negative one. I could just put that out here.