This question is similar to Chapter 2 Class 12 Inverse Trigonometric Functions Β - Ex 2.1

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https://www.teachoo.com/3041/676/Ex-2.1--6---Find-principal-value-of-tan-1-(-1)---Chapter-2-Inverse/category/Ex-2.1/

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[SQP 2026] Evaluate tan(tan^(βˆ’1) (βˆ’1)+πœ‹/3) - Sample Paper Class 12 - CBSE Class 12 Sample Paper for 2026 Boards

part 2 - Question 21 (A) - CBSE Class 12 Sample Paper for 2026 Boards - Solutions of Sample Papers and Past Year Papers - for Class 12 Boards - Class 12
part 3 - Question 21 (A) - CBSE Class 12 Sample Paper for 2026 Boards - Solutions of Sample Papers and Past Year Papers - for Class 12 Boards - Class 12

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Transcript

Question 21 (A) Evaluate tan(tan^(βˆ’1) (βˆ’1)+πœ‹/3)We have to find 𝐭𝐚𝐧(〖𝒕𝒂𝒏〗^(βˆ’πŸ) (βˆ’πŸ)+𝝅/πŸ‘) Let’s find tan^(βˆ’1) (βˆ’1) first 〖𝒕𝒂𝒏〗^(βˆ’πŸ) (βˆ’πŸ) Let y = tanβˆ’1 (βˆ’1) We know that tanβˆ’1 (βˆ’x) = βˆ’ tan βˆ’1 x y = βˆ’ tanβˆ’1 (1) y = βˆ’ 𝝅/πŸ’ Since Range of tanβˆ’1 is (βˆ’Ο€/2,Ο€/2) Hence, tanβˆ’1 (βˆ’1) = βˆ’ 𝝅/πŸ’ is correct Now, 𝒕𝒂𝒏(〖𝒕𝒂𝒏〗^(βˆ’πŸ) (βˆ’πŸ)+𝝅/πŸ‘) =π‘‘π‘Žπ‘›((βˆ’πœ‹)/4+πœ‹/3) =𝒕𝒂𝒏(𝝅/πŸ‘βˆ’π…/πŸ’) Using π‘‘π‘Žπ‘›(π΄βˆ’π΅)=(π‘‘π‘Žπ‘›β‘π΄ βˆ’ π‘‘π‘Žπ‘›β‘π΅)/(1 + π‘‘π‘Žπ‘›β‘π΄ π‘‘π‘Žπ‘›β‘π΅ ) =(π‘‘π‘Žπ‘›(πœ‹/3) βˆ’ tan⁑(πœ‹/4))/(1 + π‘‘π‘Žπ‘›(πœ‹/3) tan⁑(πœ‹/4) ) =(√3 βˆ’ 1)/(1 + √3 Γ— 1) =(√3 βˆ’ 1)/(1 + √3 ) =(βˆšπŸ‘ βˆ’ 𝟏)/(βˆšπŸ‘ + 𝟏)

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