Question

Can somebody check my work?

Answer 1

is it your hw?

Answer 2

Just the attached file.

Answer 3

i thing i noticed is that sin^2 = 1-cos^2 = 1-u^2 not u^2 -1

Answer 4

you would just be off by a neg sign though

Answer 5

Oh I see. I don't know why I substituted u=sinx x, I meant to do it for cosine. haha