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Prove that: sin 60° cos 30° + cos 60° . sin 30°  = 1 - Mathematics

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Question

Prove that:

sin 60° cos 30° + cos 60° . sin 30°  = 1

Sum

Solution

LHS =sin 60° cos 30° + cos 60°. sin 30°

= `(sqrt3)/(2) (sqrt3)/(2) + (1)/(2) (1)/(2) = (3)/(4) + (1)/(4) = 1 = 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]

APPEARS IN

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 3.1 | Page 291

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