SOLUTION: Simplify to a single trig function: (cos4x-cos2x)/(2sin3x). PLEASE HELP ME OUT AS SOON AS POSSSIBLE!!!!! Thanks in advance!!!
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-> SOLUTION: Simplify to a single trig function: (cos4x-cos2x)/(2sin3x). PLEASE HELP ME OUT AS SOON AS POSSSIBLE!!!!! Thanks in advance!!!
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Question 181021: Simplify to a single trig function: (cos4x-cos2x)/(2sin3x). PLEASE HELP ME OUT AS SOON AS POSSSIBLE!!!!! Thanks in advance!!! Answer by Mathtut(3670) (Show Source):
You can put this solution on YOUR website! Simplify to a single trig function: (cos4x-cos2x)/(2sin3x). PLEASE HELP ME OUT AS SOON AS POSSSIBLE!!!!! Thanks in advance!!!
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formula: 2 angles lets call them s and t
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formula states that cos(s)-cos(t)=-2 sin((s+t)/2) sin((s-t)/2)
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that is what we are using below:
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using formula just on the numerator, we will bring the denominator back into play below: cos4x-cos2x==-2sin((4x+2x)/2)*sin((4x-2x)/2)=-sin3x*sinx
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after using formula on numerator, we put those results back into the numerator of the original problem:
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