SOLUTION: prove that sin(pi-theta)=cos{(pi/2)-(theta)}

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Question 508179: prove that sin(pi-theta)=cos{(pi/2)-(theta)}
Answer by lwsshak3(11628) About Me  (Show Source):
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prove that sin(pi-theta)=cos{(pi/2)-(theta)}
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use x in place of theta
prove:
sin(π-x)=cos(π/2-x)
Using addition formulas for sin and cos:
sin(π-x)=sinπ cosx-cosπ sinx=0*cosx-(-1*sinx)=sinx
cos(π/2-x)=cos π/2 cosx+sin π/2 sinx=0*cosx+1*sinx=sinx
verified:
sin(π-x)=cos(π/2-x)