Evaluate: Sin 18° _________ Cos 72°

1.	Evaluate: Sin 18° _________ Cos 72°
Answer» Sin 18°upon cos 72°Sin changes to cos So ,sin(90°-18°) upon cos 72°Sin will change to cos 72 °upon cos72°Then cos 72° will cancel with cos72°The answer will be (1) Answer is zero (0)

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