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प्रश्न
`costheta/((1-tan theta))+sin^2theta/((cos theta-sintheta))=(cos theta+ sin theta)`
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उत्तर
LHS = `cos theta/((1-tan theta))-sin^2theta/((cos theta-sintheta))`
=`cos theta/((1-sintheta/costheta)) -sin^2 theta/((cos theta-sin theta))`
=`cos^2 theta/((cos theta-sintheta))- sin^2 theta/((cos theta-sin theta))`
=`(cos^2 theta- sin ^2 theta)/((cos theta- sin theta))`
=`((costheta + sin theta)( cos theta-sin theta))/((cos theta - sin theta))`
=`(cos theta + sin theta)`
= RHS
Hence, LHS = RHS
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