Question 28 (Choice - 2) - CBSE Class 10 Sample Paper for 2021 Boards - Maths Standard - Solutions of Sample Papers for Class 10 Boards

Last updated at April 16, 2024 by Teachoo

The roots α and β of the quadratic equation x ² – 5x + 3(k – 1) = 0 are such that α – β = 1. Find the value k.

The roots α and β of the quadratic equation x2 -5x+3(k-1)=0 are such

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

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

Transcript

Question 28 (Choice - 2) The roots α and β of the quadratic equation x2 – 5x + 3(k – 1) = 0 are such that α – β = 1. Find the value k.Since α and β are roots of x2 – 5x + 3(k – 1) = 0 Sum of Zeros α + β = (−(−5))/1 α + β = 5 Product of Zeros αβ = (3(𝑘 − 1))/1 αβ = 3(k − 1) Now, our equations are α + β = 5 …(1) α – β = 1 …(3) Adding both equations (α + β) + (α − β) = 5 + 1 2𝜶 = 6 𝜶 = 3 Putting 𝜶 = 3 in (1) α + β = 5 3 + β = 5 β = 5 − 3 β = 2 Now, From (2) αβ = 3(k − 1) Putting values 3 × 2 = 3(k − 1) 2 = (k − 1) 2 + 1 = k k = 3

Next: Question 29 Important → Ask a doubt

Made by

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.

Class 6

Class 7

Class 8

Class 9

Class 10

Class 11

Class 12

Courses

Interesting

Popular