Hint(I think):
sin^2(x)+cos^2(x)=1
Hello, tempq1!
. .
is in a right triangle with: .
Using Pythagorus, we find that: .
And we can now express and
To apply the correct signs to our answer, we note that:
. . is positive: is in Quadrant 1 or 4.
. . is negative: is in Quadrant 3 or 4.
. . . . Hence, is in Quadrant 4.
Go for it!