Question

The question says to evaluate the integral by making the given substitution. The integral of 5 cos(3x) dx with u=3x

Answer 1

you mean evaluate the integral by using substitution?

Answer 2

what would you substitute?

Answer 3

I don't see where you would substitute....

Answer 4

ok, how would you integrate cos(3x)?

Answer 5

The question says to evaluate the integral by making the given substitution. (u=3x)

Answer 6

\[\int\limits 5\cos(3x) dx, with (u=3x)\]

Answer 7

you are doing a U substitution
\[\int\limits 5\cos(3x) = \int\limits 5\cos(u)\]
and your dv=3, so to compensate for the 3 you need a 1/3

Answer 8

so your integral will look like this \[\int\limits 5/3 \cos(u)\] and take the integral from there and resub back in your u

Answer 9

sorry forgot the du
\[5/3 \int\limits \cos(u) du\]

Answer 10

-5/3 sin(u) + C = -5/3 sin (3x) + C

Answer 11

sorry its positive

Answer 12

How did you get the 5/3 part

Answer 13

and your dv=3, so to compensate for the 3 you need a 1/3 <-- How did you get that part?