(sec A + tan A) (1 – sin A) equals:

(a) sec AΒ Β Β Β Β Β Β Β Β Β Β Β Β Β Β Β Β Β Β Β Β Β Β  (b) sin AΒ Β Β Β Β Β Β Β Β Β Β Β Β Β Β Β Β Β  (c) cosec AΒ Β Β Β Β Β Β Β Β Β Β Β Β Β  (d) cos A

This question is similar to Example 10 - Chapter 8 Class 10 Introduction to Trignometry

[Maths Sample Paper] (sec A + tan A) (1 – sin A) equals: (a) sec A - CBSE Class 10 Sample Paper for 2024 Boards - Maths Standard

part 2 - Question 12 - CBSE Class 10 Sample Paper for 2024 Boards - Maths Standard - Solutions of Sample Papers for Class 10 Boards - Class 10

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(sec A + tan A)(1 – sin A) We write everything in terms of sin A and cos A = (1/cos⁑〖 𝐴〗 +" " sin⁑〖 𝐴〗/cos⁑〖 𝐴〗 ) (1 – sin A) = ((1 +γ€– sin〗⁑〖 𝐴〗)/cos⁑〖 𝐴〗 )(1 – sin A) = ((1 +γ€– sin〗⁑〖 𝐴) (1 βˆ’γ€– sin〗⁑〖 𝐴)γ€— γ€—)/(cos⁑ 𝐴 ) = ((12 βˆ’γ€– sin^2〗⁑〖 𝐴) γ€—)/( cos⁑〖 𝐴〗 ) = ((𝟏 βˆ’γ€– γ€–π’”π’Šπ’γ€—^πŸγ€—β‘γ€– 𝑨) γ€—)/( 𝒄𝒐𝒔⁑〖 𝑨〗 ) = cos⁑〖2 𝐴〗/( cos⁑〖 𝐴〗 ) = cos A cos2 A + sin2 A = 1 cos2 A = 1 – sin2 A ∴ 1 – sin2 A = cos2 A So, the correct answer is (d)

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Davneet Singh

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