CBSE Class 10 Sample Paper for 2025 Boards - Maths Standard
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CBSE Class 10 Sample Paper for 2025 Boards - Maths Standard
Last updated at February 12, 2025 by Teachoo
This question is similar to Chapter 4 Class 10 Quadratic Equations - Ex 4.3
Please check the question here
https://www.teachoo.com/13145/509/Ex-4.4--1-iii/category/Ex-4.4/
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![[Video solution] The roots of quadratic equation x^2 + x - 1 = 0 are - CBSE Class 10 Sample Paper for 2025 Boards - Maths Standard](https://cdn.teachoo.com/1e10572b-6b0b-4279-86b5-f1b63eaa5b61/slide27.jpg)
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Transcript
Question 11 The roots of the quadratic equation š„^2+š„ā1=0 are (A) Irrational and distinct (B) not real (C) rational and distinct (D) real and equal x2 + x ā 1 = 0 Comparing equation with ax2 + bx + c = 0 a = 1 , b = 1, c = ā1 We know that , D = b2 ā 4ac = (1)2 ā 4 Ć 1 Ć (ā1) = 1 + 4 = 5 Concept: D < 0 , no real roots D = O , two equal real roots D > 0, two distinct real roots Since D > 0 There are 2 distinct real roots Now using quadratic formula to find roots x = (ā š Ā± āš·)/2š Putting values x = (ā1 Ā± ā5)/(2 Ć 1) x = (āš Ā± āš)/š Therefore, the root of the equation are x = (āš + āš)/š & x = (āš ā āš)/š Thus, Roots are irrational Roots are distinct So, the correct answer is (A)
