Evaluate: Sin2 35° - Cos2 55° - Mathematics

Evaluate: sin² 35° - cos² 55°

Sum

sin² 35° - cos² 55°
= sin² 35° - [cos(90° - 35°)]²
= sin²35° - sin²35°
= 0

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Complementary Angles for Sine ( Sin ) and Cosine ( Cos )

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Chapter 25: Complementary Angles - Exercise 25 [Page 310]

Chapter 25 Complementary Angles
Exercise 25 | Q 2.2 | Page 310

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