Q27 of 242 Page 9

If one root of the equation ax2 + bx + c = 0 is three times the other, then b2 :ac =

In the given equation ax2 + bx + c = 0


Let α and β be the two roots


Given α = 3β ……..1


α β = (product of the roots)


3 β2 = c / a ……….. by using 1


β2 = …………….2


α + β =


4β =


Squaring both the sides


16 β2 =


By using 2


16 x =


= b2/ac

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