00:01
So first, we assume that theta does not equal 3 pi divided by 2 plus 2 pi k, where k is an integer.
00:18
And we're assuming this just so we don't end up dividing by 0.
00:23
Notice these are the only points where you could potentially end up with 0 on the left -hand side.
00:28
Okay, so let's go ahead and start with the left -hand side, like the problem suggests.
00:32
So we have 1 plus sine theta plus i cosine theta, 1 plus sine theta, minus i cosine theta.
00:53
Now, just to make everything easier to track, i'm going to include parentheses around the real parts.
01:02
And let's go ahead and take their suggestion and multiply by the conjugate of the denominator.
01:32
Okay, so working that out, we get, so on the numerator i'm going to foil it out, but i'm going to leave the real part group together.
02:03
Theta times i cosine theta plus i squared cosine theta, divided by 1 plus sine theta squared theta squared, minus i squared, cosine squared.
02:56
Okay, let's rewrite this so that we use the fact that i squared is equal to negative 1.
03:16
Oops, there's supposed to be a squared on the cosine term.
03:28
And here let's also on the denominator expand out the 1 plus sign squared.
03:53
Okay.
03:59
Now on the numerator, we're going to use a trigometric identity...