1. Chapter 8 Class 10 Introduction to Trignometry
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Question 11 - NCERT Exemplar - MCQ - Chapter 8 Class 10 Introduction to Trignometry

Last updated at Dec. 16, 2024 by Teachoo

If ∆ABC is right angled at C, then the value of cos (A + B) is

(A) 0   (B) 1   (C) 1/2    (D) √3/2

Transcript

Question 11 If ∆ABC is right angled at C, then the value of cos (A + B) is (A) 0 (B) 1 (C) 1/2 (D) √3/2 Given ∠ C = 90° Now, By Angle sum property in Δ ABC ∠ A + ∠ B + ∠ C = 180° ∠ A + ∠ B + 90° = 180° ∠ A + ∠ B = 180° − 90° ∠ A + ∠ B = 90° Now, cos (A + B) = cos 90° = 0 So, the correct answer is (A)
  1. Chapter 8 Class 10 Introduction to Trignometry
  2. Serial order wise

    3. NCERT Exemplar - MCQ

    sin 90 - θ, cos 90 - θ formula →
sin 90 - θ, cos 90 - θ formula →
Chapter 8 Class 10 Introduction to Trignometry
Serial order wise

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Davneet Singh has done his B.Tech from Indian Institute of Technology, Kanpur. He has been teaching from the past 14 years. He provides courses for Maths, Science and Computer Science at Teachoo