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MathsMediumMCQ2014 ยท 09 Apr Online

Q62.If equations ax2 + bx + c = 0, (a, b, c โˆˆR, a โ‰ 0) and 2x2 + 3x + 4 = 0 have a common root, then a : b : c equals : (1) 2 : 3 : 4 (2) 4 : 3 : 2 (3) 1 : 2 : 3 (4) 3 : 2 : 1

What This Question Tests

This question assesses the understanding of common roots between two quadratic equations, particularly when one equation has non-real roots, implying both equations must be identical up to a scalar multiple.

Concepts Tested

Discriminant of a quadratic equationCommon root condition for quadratic equations

Formulas Used

Discriminant D = b^2 - 4ac

If A1x^2+B1x+C1=0 and A2x^2+B2x+C2=0 have both roots common, then A1/A2 = B1/B2 = C1/C2

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