Given that sin t =(1/4) and that P(t) is a point in the second quadrant, what is the cos of t?

1 Answer
Mar 8, 2018

cos(t)=154

Explanation:

Given sin(t)=14

Use the identity:

cos(t)=±1sin2(t)

We are told that t is in the second quadrant and we know that the cosine function is negative in the second quadrant, therefore, we chose the negative value for the identity:

cos(t)=1sin2(t)

Substitute sin2(t)=(14)2:

cos(t)=1(14)2

cos(t)=1516

cos(t)=154