JEE Main 25 February 2021, Shift 1, Maths Q63

Question 63 of 90 in this shift, Maths question 3 of 30, Section A.

The integer 'k', for which the inequality

x^2 - 2(3k-1)x + 8k^2 - 7 > 0

is valid for every

x

in R, is :

(1)2
(2)3Official answer
(3)4
(4)0

Official answer

Option 2

NTA final key.

Chapter: Complex Numbers and Quadratic Equations
Topic: Quadratic Roots
Idea tested: Always Positive Condition

Same idea in other shifts

Asked 2× in all

2 Apr 2026, Shift 1 · Q23Let $a, b, c \in \{1, 2, 3, 4\}$ . If the probability, that $ax^2+2\sqrt2\,bx+c>0$ for all $x \in \mathbf{R}$ , is $\frac{m}{n}$ ,…MediumNumerical value

Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 108 of the 174 JEE Main shifts held from 2017 to 2026.