00:01
So here we're going to be taking the integral of x to negative fifth times l and x using integration by parts.
00:06
And the first step to any integration by parts problem is establishing what our u is and what our dv is.
00:12
So in this problem, it's easier to make u as l and x.
00:15
So let's write that here.
00:17
U is equal to l and x and our dv is going to be x to the negative fifth.
00:32
Okay, so now that we've established this, we can find d u and v.
00:36
So to find d u, we just take the derivative of both sides and so we have that du is equal to 1 over x dx.
00:50
And to find v, we have to go backwards.
00:52
So we take the integral of both sides and you take the integral of x to negative fifth.
00:56
That's going to give you negative x to the negative fourth over four.
01:03
That's using the reverse power rule...