SOLUTION: how to find the value of sin 1380 cos 225 and tan 420

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Question 750962: how to find the value of sin 1380 cos 225 and tan 420
Answer by lwsshak3(11628) About Me  (Show Source):
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how to find the value of sin 1380 cos 225 and tan 420
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1380-3*360=1380-1080=300
sin(1380)=sin(300)=sin(60)=-√3/2 (in Q4 where sin<0)
..
cos(225)=cos(45)=-√2/2 (in Q3 where cos<0)
..
420-360=60
tan(420)=tan(60)=√3 (in Q1 where tan>0)