Trig equation

Albi

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cos(3x-π/4)=sin(x)
Can someone help me solve this equation?
 

pka

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Subhotosh Khan

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Dr.Peterson

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cos(3x-π/4)=sin(x)
Can someone help me solve this equation?
I would probably start with the cofunction identity, replacing sin(x) with cos(pi/2 - x). Then you have two equal cosines, and can consider the two conditions under which the cosines of angles can be equal: either they are coterminal, or one is coterminal with the negative of the other.
 
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