00:01
In this problem we have given sicken theta is equals to minus 4 where theta is greater than 180 degree and smaller than 270 degrees.
00:18
And we are asked to find the exact value of sine theta upon 2, cosine theta upon 2 and tangent theta upon 2.
00:26
First of all we will find the value of cosine theta.
00:30
Since we know that, cosine theta is equals to 1 upon second theta.
00:38
By substituting the value of second theta we get cosine theta is equal to minus 1 upon 4.
00:46
And now we will find the value of sine theta upon 2.
00:50
Since theta upon 2 lies in the third quadrant, so, sine theta upon 2 would be equals to negative under root 1 minus cosine theta upon 2.
01:03
Now we will put the value of cosine theta we get minus under root 1 minus minus 1.
01:14
Minus 1 upon 4 upon 2.
01:17
By simplifying it we get minus under root 5 upon and root 8.
01:23
We get sine theta upon 2 is equal to minus under root 5 upon 2 under root 2...