Question

what is the integral of cos(pi*x)?

Answer 1

I know the integral of cos(x) is just sin(x), but in this case would pi affect the calculation?

Answer 2

Pi is 3.14..... so is just a constant

Answer 3

so it's just sin(pi*x)?

Answer 4

Since you have Cos(pix) then the integral would be Sin(pix)/pi +C

Answer 5

I mean cos(x) = sin(kx)/k +C

Answer 6

ah ok, I'll have to look over those rules again. Thanks for your help

Answer 7

You can also solve for u and get the same answers

Answer 8

Cos(pi*x) let u = pi*x and du = pi * dx then solve for dx-> pi/du = dx
1/pi integral of cos(u) du therefore 1/pi * sin(u) +C
combining both would be sin(u)/pi + C
then since u = pi x
sin(pi*x)/pi +C