00:01
So in this problem, we're given that the cosine of t is equal to negative one -third.
00:07
We're also given that it's in quadrant three.
00:11
So if i draw my triangle in quadrant three, one, two, three, and four, cosine is adjacent over the hypotenuse.
00:24
Because the hypotenuse is the radius, it's a distance, it will always be positive, making my cosine value, my x value, negative one, my r value, in this particular case, i just need to find out what the height of this triangle will be in order to calculate the rest of the trig functions.
00:43
I'm going to use the pythagorean theorem.
00:46
Negative 1 squared plus y squared equals 3 squared, which is 1 plus y squared is equal to 9, which is y squared is equal to 8.
00:58
So y would equal plus or minus 2 root 2.
01:04
Since it's in the third quadrant, i know that my y value has to be negative.
01:10
So this would be negative 2 root 2...