SOLUTION: Evaluate cos90+sin330+sin90+cos60. Do not use a calculator. all numbers are degrees thank youuu

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Question 1152175: Evaluate cos90+sin330+sin90+cos60. Do not use a calculator.
all numbers are degrees thank youuu
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

Evaluate
cos%2890%29%2Bsin%28330%29%2Bsin%2890%29%2Bcos%2860%29

using unit circle we get:
cos%2890%29=0
sin%28330%29=+-sin%2830%29=-1%2F2
sin%2890%29=1
cos%2860%29=1%2F2
then
cos%2890%29%2Bsin%28330%29%2Bsin%2890%29%2Bcos%2860%29
=0%2B%28-1%2F2%29%2B1%2B1%2F2
=cross%28-1%2F2%29%2B1%2Bcross%281%2F2%29
=1