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Prove that: sin 60° = 2 sin 30° cos 30° - Mathematics

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Question

Prove that:
sin 60° = 2 sin 30° cos 30°

Sum

Solution

LHS = sin 60° = `(sqrt3)/(2)`

RHS = 2 sin 60° cos 60° = `2 xx (sqrt3)/(2) xx (1)/(2) = (sqrt3)/(2)`

LHS = RHS

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Chapter 23: Trigonometrical Ratios of Standard Angles [Including Evaluation of an Expression Involving Trigonometric Ratios] - Exercise 23 (A) [Page 291]

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Selina Concise Mathematics [English] Class 9 ICSE
Chapter 23 Trigonometrical Ratios of Standard Angles [Including Evaluation of an Expression Involving Trigonometric Ratios]
Exercise 23 (A) | Q 6.1 | Page 291

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