Question

By Parts xcos7xdx

Answer 1

i think you want integration.

Answer 2

i assume ur talking about integration , so you would have :
u=x
dv=cos(7x)dx
and then use the formula \[\int\limits_{}^{}{udv}=uv-\int\limits_{}^{}{vdu}\]

Answer 3

yes

Answer 4

so can u do the next steps by urself?