00:01
For this problem, we are told that all rectangles with an area of 64 have a perimeter given by p of x equals 2x plus 128 over x, where x is the length of one side of the rectangle.
00:12
We are then told to find the absolute minimum value of the perimeter function on the interval 0 to infinity, as well as what are the dimensions of the rectangle with the minimum parameter.
00:21
So first thing that we want to do to find that absolute minimum is to take the derivative with respect to x of our perimeter function, which is going to give us 2 minus 1.
00:30
128 over x squared.
00:34
We want to find when this equals zero, so we multiply through everything by 2x squared, or by x squared rather.
00:40
So we get 2x squared minus 128 equals 0, which then in turn means that we want x squared to equal 64, which means we want x to equal plus or minus, but the minus is not meaningful.
00:55
The square root of 64, which i believe that is 8...