For what values of k, the equation 9x 2 + 6kx + 4 = 0 has equal roots?

For what values of k, the equation 9x^2 + 6kx + 4 = 0 has equal roots?

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Question 6 For what values of k, the equation 9x2 + 6kx + 4 = 0 has equal roots?Given equation 9x2 + 6kx + 4 = 0 Since it has equal roots D = 0 b2 − 4ac = 0 Putting a = 9, b = 6k, c = 4 (6k)2 − 4(9)(4) = 0 36k2 = 4 × 9 × 4 k2 = (4 × 9 × 4)/36 k2 = 4 k = ± 2 Thus, k = 2, −2

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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.