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Evaluate:"sin"pi/4"cos"pi/(12)+"cos"pi/4...

Evaluate:`"sin"pi/4"cos"pi/(12)+"cos"pi/4"sin"pi/(12)`

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`"sin"pi/4"cos"pi/(12)+"cos"pi/4"sin"pi/(12)`
`=sin(pi/4+pi/(12))=sin(3pi+pi)/(12)="sin"pi/3=sqrt3/2`
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