00:01
We want to find the arc length of e to the theta over 2 from 0 to pi over 2.
00:07
Here is the arc length in polar formula.
00:10
R theta 1 is 0, r theta 2 is pi over 2.
00:14
So r squared is e to the theta over 2 squared, which is just e to the theta.
00:23
And then dr d theta, so that is e to the u, so it is derivative e to the u du.
00:29
So e to the theta over 2 times 1 half.
00:33
So then dr d theta squared, that is e to the theta over 2 over 2 squared.
00:45
So that is e to the theta over 4.
00:53
So then r squared plus dr d theta squared is e to the theta plus e to the theta over 4.
01:07
So that is 4 over 4, so 5 fourths e to the theta...