00:01
This problem, it is said that tan t is equal to negative 3 over 4, and pi over 2 is less than t is less than pi, and we need to find the other trigonometric functions.
00:14
So, first of all, let us determine sec t.
00:19
Now, 1 plus tan square t, this will give us sec square t, using the pythagorean identity.
00:28
And we want to find sec t, so we're going to take the square root.
00:32
Take the positive or negative square root.
00:34
Well, pi over 2 is less than t is less than pi, meaning that t is in the second quadrant.
00:40
And in the second quadrant, sec is negative.
00:42
So we have negative the square root of 1 plus 10 square root of 1 plus negative 3 over 4 whole squared.
00:50
So negative square root of 1 plus 9 over 16.
00:56
That's negative the square root of 16 plus 9, which is 25 divided by 16.
01:01
So we have.
01:02
Negative 5 over 4 and so that is the value of sec t now we can determine cost t as one divided by sec t so that will be one divided by negative 5 over 4 so this is negative 4 over 5 so that's cost t now let us determine sine t so what is sign t well sine t can be obtained as tan t times cost t this is because tan t is sine t over cost t and tan t is negative 3 over 4, and we calculated cost t to be negative 4 over 5.
01:37
So we are left with 3 over 5, that is sine t.
01:41
And we can use that to find kosek t...