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Prove that: cosec2 45°  - cot2 45°  = 1 - Mathematics

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Question

Prove that:

cosec2 45°  - cot2 45°  = 1

Sum

Solution

LHS= cosec2 45° - cot2 45°

= `(sqrt2)^2 –1^2 = 2  – 1 = 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 3.3 | Page 291

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