How to solve sin (180°+α) sin (90°-α)? How does sin change to

prove the following with diagram 1) sin(90-A)=cosA 2)cos(90+A)=-sinA 3)sin( 180+A)=-sinA - pm8v54ww

How to solve sin (180°+α) sin (90°-α)? How does sin change to cosine - Quora

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How to solve sin (180°+α) sin (90°-α)? How does sin change to cosine - Quora

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