SOLUTION: Hi! The question I need help with is: If sin θ = 1/2, then cos θ = ? I'm not really sure how to go about answering the question because I don't understand sine and cosine

Algebra ->  Trigonometry-basics -> SOLUTION: Hi! The question I need help with is: If sin θ = 1/2, then cos θ = ? I'm not really sure how to go about answering the question because I don't understand sine and cosine      Log On


   

Question 808238: Hi! The question I need help with is: If sin θ = 1/2, then cos θ = ? I'm not really sure how to go about answering the question because I don't understand sine and cosine at all. I do have a graphing calculator on hand and its a TI-84, in case there are any specificities in your instructions for people with certain types of calculators. Thank you in advance for your help!
-Kyli
Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
sin Theta=1/2
sin^2 theta =+1%2F4

sin^2theta+cos^2theta=1
substitute sin^2theta
1/4 + cos^2theta =1
cos^2theta = 1-1/4
cos^2theta = 3/4
take square root
costheta = sqrt%283%29%2F2