00:01
So given the function f of x equals x for x plus one, first what would my domain be? and remember domain is just what i can input into the function.
00:09
So what can i input? well, my only restrictions are zero in the denominator or a square root.
00:16
Here i have a denominator can't be equal to zero.
00:19
So it's all x values such that x can't be negative one to make my denominator zero.
00:25
What's f of fx? well, this is what happens when i just plug in f of x, which is x over x plus 7, x over x plus 1, into my function.
00:37
So i'm just replacing all my x terms with x over x plus 1, all over x over x plus 1, plus 1.
00:49
Now i have a denominator.
00:51
I'm going to multiply by x plus 1 to the top and bottom, just to simplify.
00:55
I could do this because this is technically multiplied by 1.
00:59
This will cancel up top, so this will be x.
01:01
Distribute this will be x plus 1 times x plus 1, which will be x over 1 plus x is 2x plus 1...