SOLUTION: If sin A= -1/squareroot of 5 with A in QII, find sin 2A.

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Question 961016: If sin A= -1/squareroot of 5 with A in QII, find sin 2A.
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
If sin A= -1/squareroot of 5 with A in QII, find sin 2A
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sinA=-1%2Fsqrt%285%29=-sqrt%285%29%2F5

sin2A=2cosAsinA=2*√5/5*2√5/5=20/25=4/5