Suppose tan(θ) is undefined and sin(θ) < 0. Find the exact values of the 6 trigonometric functions of the angle θ?

Suppose tan(θ) is undefined and sin(θ) < 0. Find the exact values of the 6 trigonometric functions of the angle θ.

1 Answer
May 3, 2018

#sin((3pi)/2)=-1#
#cos((3pi)/2) = 0#
#tan((3pi)/2)# is undefined
#csc((3pi)/2) = -1#
#sec((3pi)/2)# is undefined
#cot((3pi)/2) = 0#

Explanation:

Since the tangent is undefined, we must assume that #cos(theta)=0#. this only happens if #theta = pi/2# or #theta=(3pi)/2#

But we also know that #sin(theta)<0#. Since #sin(pi/2)=1# and #sin((3pi)/2)=-1#, we know that #theta=(3pi)/2#.