SOLUTION: If sinx + cosx = 3/4 find sinx - cosx

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Question 1090355: If sinx + cosx = 3/4 find sinx - cosx
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
If sinx + cosx = 3/4
sin^2 + 2sin*cos + cos^2 = 9/16
1 + sin(2x) = 9/16
sin(2x) = -7/16
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find sinx - cosx
(sin - cos)^2 = sin^2 - sin(2x) + cos^2 = 1 - sin(2x)
= 1 - (-7/16) = 23/16
sin - cos = sqrt(23)/4
or -sqrt(23)/4
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Clever?