If one root of the quadratic equation 3x 2 + px + 4 = 0 is 2/3, then find
the value of p and the other root of the equation.

If one root of the quadratic equation 3x2+px+4=0 is 2/3, then find

Question 28 (Choice - 1) - CBSE Class 10 Sample Paper for 2021 Boards - Maths Standard - Part 2
Question 28 (Choice - 1) - CBSE Class 10 Sample Paper for 2021 Boards - Maths Standard - Part 3

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Question 28 (Choice - 1) If one root of the quadratic equation 3x2 + px + 4 = 0 is 2/3, then find the value of p and the other root of the equation.Since one root is 2/3 Putting 𝟐/𝟑 in equation 3x2 + px + 4 = 0 3(2/3)^2+𝑝 ×2/3+4=0 3 ×4/9+𝑝 ×2/3+4=0 4/3+𝑝 ×2/3+4=0 4/3+4+ 𝑝 ×2/3=0 (4 + 16)/3+ 𝑝 ×2/3=0 20/3+ 𝑝 ×2/3=0 𝑝 ×2/3=−20/3 𝑝 =−20/3 ×3/2 𝒑 = −10 Thus, our equation becomes 3x2 + px + 4 = 0 3x2 − 10x + 4 = 0 Now, Product of Roots = 𝟒/𝟑 First Root × Second Root = 4/3 2/3 × Second Root = 4/3 Second Root = 4/3 ×3/2 Second Root = 2

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