00:01
This problem is given the function g of z, and we're being asked to find g of 2 minus 3i.
00:05
What i'm going to do first, though, is i'm going to simplify our g of z function.
00:09
So i'm going to factor the numerator.
00:11
Well, i notice that i have a greatest common factor of z squared, so i'll factor that out.
00:16
And when i do that, i'm left with z squared minus 1, and it's still getting divided by z minus 1.
00:22
But if you notice, z squared minus 1 is the difference of two squares.
00:26
So this is going to factor the z squared times z plus 1 times z minus 1.
00:34
And if you now notice, we have a z minus 1 factor in the numerator and denominator.
00:38
So these will cancel.
00:40
So we're just left with z squared times z plus 1.
00:45
Now that we've simplified, let's go ahead and substitute 2 minus 3i in place of z.
00:50
So when we do this, we're going to be left with the quantity of 2 minus 3i squared times the quantity of 2 minus 3i plus 1.
01:02
So off to the side, i'm going to do 2 minus 3 i squared.
01:07
Well, when we multiply this out, we're going to be left with, we don't need a preemphasy there, 4 minus 12 i plus 9 i squared...