In the given figure, D is the mid-point of BC, then the value of cot 𝑦 ° cot π‘₯ ° is

(a) 2   (b) 1/2  (c) 1/3  (d) 1/4

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Question 32 In the given figure, D is the mid-point of BC, then the value of cot 𝑦 Β° cot π‘₯ Β° is (a) 2 (b) 1/2 (c) 1/3 (d) 1/4 Since D is mid-point of BC Let CD = BD = a Now, π’„π’π’•β‘γ€–π’šΒ°γ€—/𝒄𝒐𝒕⁑〖𝒙°〗 = (1/tan⁑〖𝑦°〗 )/(1/tan⁑〖π‘₯Β°γ€— ) = 1/tan⁑〖𝑦°〗 Γ—tan⁑〖π‘₯Β°γ€—/1 = 𝒕𝒂𝒏⁑〖𝒙°〗/π’•π’‚π’β‘γ€–π’šΒ°γ€— Now, tan xΒ° tan⁑〖π‘₯Β°γ€—=𝐢𝐷/𝐴𝐢 =𝒂/𝑨π‘ͺ tan yΒ° tan⁑〖𝑦°〗=𝐢𝐡/𝐴𝐢 =(π‘Ž + π‘Ž)/𝐴𝐢 =πŸπ’‚/𝑨π‘ͺ Now, π’„π’π’•β‘γ€–π’šΒ°γ€—/𝒄𝒐𝒕⁑〖𝒙°〗 = π‘‘π‘Žπ‘›β‘γ€–π‘₯Β°γ€—/π‘‘π‘Žπ‘›β‘γ€–π‘¦Β°γ€— = (π‘Ž/𝐴𝐢)/(2π‘Ž/𝐴𝐢) = π‘Ž/𝐴𝐢 Γ— 𝐴𝐢/2π‘Ž = π‘Ž/2π‘Ž = 𝟏/𝟐 So, the correct answer is (b)

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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