Quantitative Aptitude – Algebra – Quadratic Equations – The minimum possible value

January 1st, 2020 by

Quantitative Aptitude - Algebra - Quadratic Equations - The minimum possible value Quantitative Aptitude - Algebra - Quadratic Equations Question The minimum possible value of the sum of the squares of the roots of the equation x^2 + (a + 3)x - (a + 5) = 0 is A) 1 B) 2 C) 3 D) 4 Answer Option (C) Solution From CAT 2017 - Quantitative Aptitude - Algebra - Quadratic Equations, we can see that, b and c can be the roots of the given equation. We have to find, b^2 + c^2 = (b+c)^2 – 2bc b+c = -(a+3) and bc = -(a+5) b^2 +

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Quantitative Aptitude – Algebra – Quadratic Equation – If x + 1 = x^2

December 30th, 2019 by

Quantitative Aptitude - Algebra - Quadratic Equation - If x + 1 = x^2 Quantitative Aptitude - Algebra - Quadratic Equation Question If x + 1 = x^2 and x > 0, then 2x^4 is A) 6 + 4√5 B) 3 + 5√5 C) 5 + 3√5 D) 7 + 3√5 Answer Option (D) Solution As per CAT 2017 - Quantitative Aptitude - Algebra - Quadratic Equation, we can see that x+1=x^2 Find out the roots of x = [1+/- root(5)]/2 X2 = [3 +/- √5]/2 X4 = [7 +/-3√5]/2 2x4 = 7 +/- 3√5 As the only option is 7 + 3√5 So, we go with that. Option (D) Down

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Quantitative Aptitude – Algebra – Quadratic Equations – If a and b are integers such that 2x^2

December 23rd, 2019 by

Quantitative Aptitude – Algebra - Quadratic Equations – If a and b are integers such that 2x^2 Slot -2 – Quantitative Aptitude – Algebra - Quadratic Equations – If a and b are integers such that 2x^2 If a and b are integers such that 2x^2 −ax + 2 > 0 and x^2 −bx + 8 ≥ 0 for all real numbers x, then the largest possible value of 2a−6b is? Answer: 36 Solution: Given, 2x^2 −ax + 2 > 0 2{ (x-a/4)^2 - a^2/16+1} > 0 ∀ x ∈R -a^2/16+1 > 0 a ∈{ -3,-2,-1,0,1,2,3} x^2 −bx + 8 ≥ 0 (

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