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Saturday, 31 October

JEE Main 2023 · MathsNumerical answerNumerical valueHardMulti-step

JEE Main 8 April 2023, Shift 2, Maths Q22

Question 22 of 90 in this shift, Maths question 22 of 30, Section B.

Let mm and nn be the numbers of real roots of the quadratic equations x2−12x+[x]+31=0x^2 - 12x + [x] + 31 = 0 and x2−5∣x+2∣−4=0x^2 - 5|x + 2| - 4 = 0 respectively, where [x][x] denotes the greatest integer ≤x\leq x. Then m2+mn+n2m^2 + mn + n^2 is equal to __________.

Official answer

9

NTA final key.

Same idea in other shifts

Asked 12× in all
  1. 8 Apr 2025, Shift 2 · Q2The sum of the squares of the roots of ∣x−2∣2+∣x−2∣−2=0|x-2|^2 + |x-2| - 2 = 0 and the squares of the roots of x2−2∣x−3∣−5=0x^2 - 2|x-3| - 5 = 0, isMediumSingle correct
  2. 5 Apr 2024, Shift 1 · Q22The number of distinct real roots of the equation ∣x∣∣x+2∣−5∣x+1∣−1=0|x||x+2|-5|x+1|-1=0 is ________.MediumNumerical value
  3. 8 Apr 2024, Shift 2 · Q21The number of distinct real roots of the equation ∣x+1∣ ∣x+3∣−4∣x+2∣+5=0|x+1|\,|x+3| - 4|x+2| + 5 = 0, is ________MediumNumerical value
  4. 30 Jan 2024, Shift 2 · Q22The number of real solutions of the equation x(x2+3∣x∣+5∣x−1∣+6∣x−2∣)=0x\left(x^2 + 3|x| + 5|x-1| + 6|x-2|\right) = 0 is ________.MediumNumerical value
  5. 13 Apr 2023, Shift 1 · Q2The set of all a∈Ra \in \mathbb{R} for which the equation x∣x−1∣+∣x+2∣+a=0x|x-1|+|x+2|+a=0 has exactly one real root, isHardSingle correct
  6. 15 Apr 2023, Shift 1 · Q2The number of real roots of the equation x∣x∣−5∣x+2∣+6=0x|x|-5|x+2|+6=0, isMediumSingle correct
  7. 30 Jul 2022, Shift 2 · Q81The number of solutions of the equation ∣x2+3x+2∣+∣x+5∣−2=0|x^2 + 3x + 2| + |x + 5| - 2 = 0, x∈Rx \in \mathbb{R}, is ________.MediumNumerical value
  8. 24 Feb 2021, Shift 2 · Q90The number of the real roots of the equation (x+1)2+∣x−5∣=274(x+1)^2+|x-5|=\frac{27}{4} is ________.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.