If −1 is a zero of the polynomial p(x) = x 2   − 7x − 8 , then the other zero is

(a) −8  (b) −7     (c) 1       (d) 8

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Question 17 If −1 is a zero of the polynomial p(x) = x2 − 7x − 8 , then the other zero is (a) −8 (b) −7 (c) 1 (d) 8 Given p(x) = x2 − 7x − 8 Since −1 is zero of polynomial Let 𝛼 = −1, and 𝛽 be zeros of p(x) Now, Product of Zeros = 𝑐/𝑎 −1 × 𝛽 = (−8)/1 𝛽 = 8 Thus, other zero is 8 So, the correct answer is (d)

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Davneet Singh

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, Social Science, Physics, Chemistry, Computer Science at Teachoo.