1. Why does the derivitive of y= (cos^2(x) + sin^2(x))^6 equal 0? I don't see how it turns out that way. 2. Why does the integral of (1/(x+3)^3 with the lower boundary 2 and upper 5 equal 39/3200? 3. Finally, I don't understand how to integrate: [sq rt(ln x)/x] because I can't figure out how to make it work with the F'(x)/F(x) rule. Thanks, I just need to understand these 3 before the exam tomorrow!