SOLUTION: Please help me with this question: Given sinΘ= -3/5, find cos 2Θ thanks

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Question 914690: Please help me with this question:
Given sinΘ= -3/5, find cos 2Θ
thanks
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
Given sinΘ= -3/5, find cos 2Θ
cos 2Θ=1-2sin^2Θ=1-2(-3/5)^2=1-2(9/25)=1-(18/25)=7/25
cos 2Θ=7/25