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Prove that: (i) cos A cos(60^(@)-A)c...

Prove that:
(i) `cos A cos(60^(@)-A)cos (60^(@)+A)=(1)/(4)cos 3A`
(ii) `"tan" A+"tan"(60^(@)+A)-"tan"(60^(@)-A)=3 tan 3A`.

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MODERN PUBLICATION-TRIGONOMETRY-Exercise 3(g)Long Answer type Question-I
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