00:01
Okay, so we know that the length of a curve, f of x, over an interval a, b is, well, is given by the integral from a to b of the square root of 1 plus the derivative here, f prime of x squared, dx.
00:18
So here we have that a is equal to 0, and we have that b is equal to 8, and we have that our function f of x is equal to x, is equal to, to 4 minus x to the two thirds to the three halves.
00:40
Okay? so we think we go ahead and we need to find, well, f prime of x, right? and then square.
00:49
So the square root.
00:49
So the f prime of x is going to be equal to negative the square root of 4 minus x to to the two thirds over x to the one third.
01:08
Okay, so now, well, the curve here is given by the integral from a to b.
01:13
So the integral from 0 to 8 of the square root of 1 plus the derivative square.
01:22
So 1 plus a negative 4 minus x to the 2 thirds all over x to the 1 third...