00:01
Okay, so for problems like number one, we are given f of x is 4x plus 8, and g of x is 7 minus x squared.
00:15
We want to find f of g of 0, and then we want to find g of f of zero.
00:23
So you work inside out.
00:25
We first want g of 0, so that's 7 minus 0 squared, which is 7 minus 0, which is then what you're going to do is you're going to replace g of 0 with what it equals.
00:37
So now you want f of 7, which is 4 times 7 plus 8 or 28 plus 8, which is 36.
00:48
Now you want to go the other way.
00:50
So we want to start with f of 0.
00:54
That's 4 times 0 plus 8, which is 8.
00:59
Now we want g of 8, which is 7 minus 7.
01:03
8 squared or 7 minus 64, which is just going to give us negative 57.
01:13
And that's how you would do the top section.
01:17
Now in the next section, we have this table.
01:21
And for number 5, for example, we want f of g of 8.
01:25
So what that tells us is find the value of g when the input is 8.
01:32
So g of 8 is 4.
01:34
Which now means we want f of 4.
01:38
So go to 4 and now find the f value.
01:42
That's going to give you 4.
01:44
Let's try a couple more.
01:47
F of g of 5.
01:49
Start with g of 5, go to 5.
01:52
Look in the g column, that's 8...