00:01
We are given a curve, and we're asked to set up an integral that represents the length of this curve, and then to use a calculator to find this length, correct to four decimal places.
00:12
So the curve is y equals x, e to the negative x, on the interval 0 to 2.
00:24
So, because y is equal to x, e, the negative x, we have that d, y, dx.
00:32
By the product rule, this is going to be e to the negative x, and then plus x, e to the negative x, so minus x, e to the negative x.
00:50
And this can, of course, be written as e to the negative x times 1 minus x.
01:00
And therefore, it follows that 1 plus, 1 plus, d, y, d x squared...