SOLUTION: Suppose that sin(theta)=-2/3, and the terminal side of (theta) lies in quadrant 4. What is the value of cos(theta)?

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Question 364262: Suppose that sin(theta)=-2/3, and the terminal side of (theta) lies in quadrant 4. What is the value of cos(theta)?
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
%28sin%28theta%29%29%5E2%2B%28cos%28theta%29%29%5E2=1
%28-2%2F3%29%5E2%2B%28cos%28theta%29%29%5E2=1
4%2F9%2B%28cos%28theta%29%29%5E2=1
%28cos%28theta%29%29%5E2=9%2F9-4%2F9
%28cos%28theta%29%29%5E2=5%2F9
cos%28theta%29=0+%2B-+sqrt%285%29%2F3
Since it lies in QIV, then
highlight%28cos%28theta%29=sqrt%285%29%2F3%29