4. If the cosecant of a fourth quadrant angle is –π/e, what is its cosine? Thanks

1 Answer
Feb 3, 2018

#cos(theta) = sqrt(pi^2-e^2)/pi#

Explanation:

Since #csc(theta) = -pi/e#, we can use Pythagorean theorem to find the missing side in a #e, x, pi# triangle:

#x=sqrt(pi^2-e^2)#

So the ordered pair through which the angle passes is #(sqrt(pi^2-e^2), -e)#.

#cos(theta) = x/r = sqrt(pi^2-e^2)/pi#