SOLUTION: sin3x + cos3x ----------- - = 1-sinxcosx sinx + cosx prove this identity

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Question 63372: sin3x + cos3x
------------- = 1-sinxcosx
sinx + cosx
prove this identity
Answer by venugopalramana(3286) About Me  (Show Source):
You can put this solution on YOUR website!
sin3x + cos3x
------------- = 1-sinxcosx
sinx + cosx
prove this identity
PLEASE CHECK YOUR PROBLEM.IT IS NOT AN IDENTITY...IT IS AN EQN. TRUE FOR SAY X=0
BUT IF YOU WANT IT TO BE PROVED AS AN IDENTITY IT IS NOT SO...FOR EX AT X=30 DEGREES WE GET
LHS = [SIN(90)+COS(90)]/[SIN(30)+COS(30)]=1/[{1+SQRT(3)}/2]=2/{SQRT(3)+1}
=SQRT(3) - 1
RHS = 1- SIN(30)*C0S(30)=1-SQRT(3)/4=[4-SQRT(3)]/4
LHS IS NOT EQUAL TO RHS