00:01
All right, question 173 wants us to convert y equals 4x squared to polar.
00:05
And so since we know that x is r cosine theta and y is r sine of theta, i'm just going to plug those into each spot.
00:12
So since y is r -sign theta, that's really right on the left side, and then i do 4 times r -cosine theta and i square it.
00:22
Okay, so what that means is i have r -sign of theta equals 4 r -squared, cosine, squared, of theta.
00:30
Like that.
00:31
Okay.
00:31
And so what i need to do is i need a solve for r.
00:34
So what i'm going to do is i'm going to move this to the other side by subtracting it.
00:38
So minus r sine of theta, right? because i'm going to subtract it from both sides.
00:43
That means i get a zero equals for r squared cosine squared theta minus r sine theta.
00:51
Okay.
00:51
And i know this looks really ugly, but we're going to simplify it.
00:54
Okay.
00:54
When there's something in common, i can factor it out.
00:57
So i do zero.
00:57
Oops, not theta...