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find the value of: cosec2 60° - tan2 30° - Mathematics

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Question

find the value of: cosec2 60° - tan2 30°

Sum

Solution

cosec2 60° – tan2 30° = `(2/sqrt3)^2 – (1/sqrt3)^2 = (4)/(3) – (1)/(3) = 1`

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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 1.4 | Page 291

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