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

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

  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 + π‘‘π‘Žπ‘›2𝐴)/(1 + π‘π‘œπ‘‘2𝐴) sec2 A (B) –1 (C) cot2 A (D) tan2 A (1 + π‘‘π‘Žπ‘›2𝐴)/(1 + π‘π‘œπ‘‘2𝐴) = (1 + 𝑠𝑖𝑛2𝐴/( π‘π‘œπ‘ 2 𝐴))/(1 + π‘π‘œπ‘ 2𝐴/(𝑠𝑖𝑛2 𝐴)) = ((π‘π‘œπ‘ 2 𝐴 + 𝑠𝑖𝑛2 𝐴)/(π‘π‘œπ‘ 2 𝐴))/((𝑠𝑖𝑛2 𝐴 + π‘π‘œπ‘ 2 𝐴)/𝑠𝑖𝑛2𝐴) = (π‘π‘œπ‘ 2 𝐴 + 𝑠𝑖𝑛2 𝐴)/(π‘π‘œπ‘ 2 𝐴) Γ— (𝑠𝑖𝑛2 𝐴)/(π‘π‘œπ‘ 2 𝐴 + 𝑠𝑖𝑛2 𝐴) = 1/(π‘π‘œπ‘ 2 𝐴) Γ— (𝑠𝑖𝑛2 𝐴)/1 = (𝑠𝑖𝑛2 𝐴)/(π‘π‘œπ‘ 2 𝐴) = ((𝑠𝑖𝑛 𝐴)/(π‘π‘œπ‘  𝐴))^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.