
Ex 7.8
Last updated at Dec. 16, 2024 by Teachoo
Ex 7.8, 21 Choose the correct answer β«_1^(β3)βππ₯/(1 + π₯^2 ) equals (A) π/3 (B) 2π/3 (C) π/6 (D) π/12 Let F(π₯)=β«1βππ₯/(1 + π₯^2 ) =tan^(β1)β‘π₯ Hence, F(π₯)=π‘ππ^(β1) π₯ Now β«_1^(β3)βγππ₯/(1 + π₯^2 )=πΉ(β3)βπΉ(1) γ =tan^(β1)β‘γβ3βtan^(β1)β‘(1) γ =π/3βπ/4 =π/12 β΄ Option (D) is correct.