So f of 1 is the square root of 1 minus 1, so that is just going to be 0. This expression right over here is going to be 2 times the square root of 2 minus 1. The square root of 2 minus 1 is just 1, so this is just going to be 2. Actually, let me do it in that same... Well, I'm now using the purple for a different purpose than just the first trapezoid. Hopefully you realize that. I was just sticking with that pen color. Then f of 3, 3 minus 1 is 2, square root of 2.