00:01
Okay, folks, so now we're going to take look at this problem, problem number 17 on your book.
00:09
This is a line integral.
00:10
We have this function, f, which is a function of position.
00:14
Let me write down the function here.
00:17
X plus y plus z divided by x squared plus y squared plus y squared plus z squared.
00:27
Okay, so we have this function here.
00:31
We would like to integrate over the path, which is given by r, parameterized by the variable t.
00:41
I'm going to write it this way.
00:42
We have t for x and t for j and t for k.
00:49
X, y, and z are both functions of t, and they're both the same function.
00:54
They're both t.
00:56
And we're going to, t is going to range from a, all the way to b.
01:06
So this is a very simple problem.
01:09
We're just going to write it this way.
01:13
We're going to integrate along the curve of f multiplied by ds.
01:21
That's the idea.
01:26
Along the curve, because f is a function of x, y, and z, but x, y, and z are all functions of t.
01:32
So let me rewrite the function as a function of t...
