00:01
So we are given that f of x is equal to x to the three halves, and that g of x is equal to 2 over x plus 1.
00:15
We're asked to evaluate various values of f of g and g of f.
00:19
For the first one, f of g of four, we find out g of four, and then plug the answer into f.
00:24
What g of four is 2 over 4 plus 1 or 2 5ths.
00:28
So we'll plug 2 5th into f.
00:33
F of two -fifths is equal to two -fifths to the power of three halves, which is the same as cubing both terms and then taking the square root of both of them.
00:44
So two cubed is eight, so that would be square root eight, and then five cubed is 125, the square root, so that would be square root eight over square root 125.
01:00
We cannot have this as an answer, though, because it is not rational.
01:04
So we'll just multiply both sides by 125.
01:08
So we can have 125, sorry, square root 125.
01:13
It's a square root 125 times square root 8 over 125.
01:18
And that will be the answer for the first one...