SOLUTION: Simplfy: cos((3*)/4+x)+ sin((3*)/4-x) Note: * = pie

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Question 206780: Simplfy: cos((3*)/4+x)+ sin((3*)/4-x)
Note: * = pie
Answer by RAY100(1637) About Me  (Show Source):
You can put this solution on YOUR website!
cos{ (3pi/4) +x} +sin { (3pi/4) -x}
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The ref angle for (3pi/4) = pi/4
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cos { (3pi/4 +x} = -cos (pi/4 -x),,,as long as x .
sin { (3pi/4)-x} = sin (pi/4 +x)
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-cos (pi/4-x) + sin(pi/4 +x)
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sin(pi/4 +x) - cos(pi/4-x)
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Discussion: it is tempting to use the "sum and difference identities"
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but this does not appear to "simplify"
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Realizing that (pi/4) is 45 degrees, this is not a bad simplification