Question 1 (ii) - Ex 8.3 - Chapter 8 Class 10 Introduction to Trignometry

Last updated at August 14, 2026 by

Ex 8.4, 3 - Chapter 8 Class 10 Introduction to Trignometry - Part 2

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Ex 8.3, 3 Evaluate : sin 25 cos 65 + cos 25 sin 65 sin 25 cos 65 + cos 25 sin 65 = sin (90 65) cos 65 + cos (90 65) sin 65 = cos 65 cos 65 + sin 65 sin 65 = cos265 + sin265 = 1 Hence, sin65 cos 65 + cos 25 sin 65 = 1

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