Question

U-substitution of sin4xcos4xdx. I'm unsure where to start with this.
I tried making my u, 4x and du 4dx. I dont know where to go after that.

Answer 1

use sin(2p)=2sin(p)cos(p)

Answer 2

sin4xcos4x = 1/2 sin8x

Answer 3

If you don't like that, just use the sub sin(4x) or you can even use the sub cos(4x).
I like the way RadEn and I thought on it initially though.

Answer 4

Yeah I'm not that great at this topic. I don't really understand so far...