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Find the value of: sin2 30° + cos2 30°+ cot2 45° - Mathematics

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Question

find the value of: sin2 30° + cos2 30°+ cot2 45°

Sum

Solution

sin2 30° + cos230° + cot2 45° = `(1/2)^2 + (sqrt3/2)^2 + 1^2`

= `(1)/(4) + (3)/(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 1.5 | Page 291

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