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find the value of: cos2 60° + sin2 30° - Mathematics

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Question

find the value of: cos2 60° + sin2 30°

Sum

Solution

cos2 60° + sin2 30° = `(1/2)^2 + (1/2)^2 = (1)/(4) + (1)/(4) = (1)/(2)`

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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 1.3 | Page 291

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