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Prove that : sin 54⁰+ cos 36⁰= √2 cos 9⁰ |
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Answer» ∘ cos54 ∘ −sin36 ∘ sin54 ∘ =0 ∘ −54 ∘ )cos(90 ∘ −36 ∘ )−sin36 ∘ sin54 ∘
=sin54 ∘ sin36 ∘ −sin36 ∘ sin54 ∘
=sin36 ∘ sin54 ∘ −sin36 ∘ sin54 ∘ =0 |
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