Ex 8.4, 4 - Chapter 8 Class 10 Introduction to Trignometry - Part 5

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Ex 8.4, 4 - Chapter 8 Class 10 Introduction to Trignometry - Part 6

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  1. Chapter 8 Class 10 Introduction to Trignometry (Term 1)
  2. Serial order wise

Transcript

Ex 8.4, 4 Choose the correct option. Justify your choice. (iv) (1 + ๐‘ก๐‘Ž๐‘›2๐ด)/(1 + ๐‘๐‘œ๐‘ก2๐ด) sec2 A (B) โ€“1 (C) cot2 A (D) tan2 A (1 + ๐‘ก๐‘Ž๐‘›2๐ด)/(1 + ๐‘๐‘œ๐‘ก2๐ด) = (1 + ๐‘ ๐‘–๐‘›2๐ด/( ๐‘๐‘œ๐‘ 2 ๐ด))/(1 + ๐‘๐‘œ๐‘ 2๐ด/(๐‘ ๐‘–๐‘›2 ๐ด)) = ((๐‘๐‘œ๐‘ 2 ๐ด + ๐‘ ๐‘–๐‘›2 ๐ด)/(๐‘๐‘œ๐‘ 2 ๐ด))/((๐‘ ๐‘–๐‘›2 ๐ด + ๐‘๐‘œ๐‘ 2 ๐ด)/๐‘ ๐‘–๐‘›2๐ด) = (๐‘๐‘œ๐‘ 2 ๐ด + ๐‘ ๐‘–๐‘›2 ๐ด)/(๐‘๐‘œ๐‘ 2 ๐ด) ร— (๐‘ ๐‘–๐‘›2 ๐ด)/(๐‘๐‘œ๐‘ 2 ๐ด + ๐‘ ๐‘–๐‘›2 ๐ด) = 1/(๐‘๐‘œ๐‘ 2 ๐ด) ร— (๐‘ ๐‘–๐‘›2 ๐ด)/1 = (๐‘ ๐‘–๐‘›2 ๐ด)/(๐‘๐‘œ๐‘ 2 ๐ด) = ((๐‘ ๐‘–๐‘› ๐ด)/(๐‘๐‘œ๐‘  ๐ด))^2 = tan2 A Answer = tan2 A Hence, option (D) is correct

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Davneet Singh
Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 10 years. He provides courses for Maths and Science at Teachoo.