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Ex 2.2
Ex 2.2, 2 Important Deleted for CBSE Board 2023 Exams
Ex 2.2, 3 Deleted for CBSE Board 2023 Exams
Ex 2.2, 4 Important Deleted for CBSE Board 2023 Exams
Ex 2.2, 5 Important Deleted for CBSE Board 2023 Exams
Ex 2.2, 6 Deleted for CBSE Board 2023 Exams
Ex 2.2, 7 Important Deleted for CBSE Board 2023 Exams
Ex 2.2, 8 Important Deleted for CBSE Board 2023 Exams
Ex 2.2, 9 Deleted for CBSE Board 2023 Exams
Ex 2.2, 10 Important Deleted for CBSE Board 2023 Exams
Ex 2.2, 11 Deleted for CBSE Board 2023 Exams
Ex 2.2, 12 Important Deleted for CBSE Board 2023 Exams
Ex 2.2, 13 Important Deleted for CBSE Board 2023 Exams
Ex 2.2, 14 Important Deleted for CBSE Board 2023 Exams
Ex 2.2, 15 Important Deleted for CBSE Board 2023 Exams
Ex 2.2, 16 Deleted for CBSE Board 2023 Exams
Ex 2.2, 17 Deleted for CBSE Board 2023 Exams
Ex 2.2, 18 Important Deleted for CBSE Board 2023 Exams
Ex 2.2, 19 (MCQ) Important Deleted for CBSE Board 2023 Exams You are here
Ex 2.2, 20 (MCQ) Important Deleted for CBSE Board 2023 Exams
Ex 2.2, 21 (MCQ) Deleted for CBSE Board 2023 Exams
Last updated at March 30, 2023 by Teachoo
Ex 2.2, 19 Find the values of cos−1(cos 7π/6) is equal to (A) 7π/6 (B) 5𝜋/6 (C) 𝜋/3 (D) 𝜋/6 Let y = cos−1 (cos 7π/6) cos y = cos (7π/6) cos y = cos (210°) Since Range of of cos−1 is [0, π] i.e. [0° ,180°] Hence, y = 210° not possible Now, cos y = cos (210°) cos y = cos (360° – 150°) cos y = cos (150°) cos y = cos (𝟓𝝅/𝟔) Hence, y = 𝟓𝝅/𝟔 Which is in the range of principal value of cos-1 i.e. [0, π] Hence , cos −1 (cos 7π/6) = 5𝜋/6 Thus, option (B) is correct (As cos (360° – θ) = cos θ)