00:01
In this problem, we want to perform several manipulations on complex numbers.
00:05
So first we want to add two complex numbers.
00:07
2 minus 2i plus 2 plus 7i.
00:10
So how we add complex numbers is we add their imaginary parts together, and then we add their real parts together.
00:19
So the 2 and the 2 here are both real.
00:22
These can be added together.
00:25
And the minus 2i and the 7i are both imaginary.
00:28
Those two can be added together.
00:29
Together.
00:31
And we obtain 4 plus 5i.
00:37
Next we have 2 minus 2i minus 2 plus 7i.
00:42
Our real parts are going to cancel in this case and we obtain simply minus 9i.
00:57
Next we have 2 minus 2i times 2 times 7i.
01:01
So what we do here is we're going to distribute like normal.
01:03
Being mindful that i squared is equal to minus 1 so we obtain after distribution 4 plus 14i minus 4i minus 14i squared where minus 14i squared simplifies to plus 14...