Q31 of 242 Page 9

If y = 1 is a common root of the equations ay2 + ay + 3 = 0 and y2 + y + b = 0, then ab equals

If y = 1 is root of both the equation it will staify both the equations

Putting y = 1 in first equation


ay2 + ay + 3 = 0


2a + 3 = 0


a =


Putting value of y in second equation


2 + b = 0


B = – 2


Now ab = x – 2


ab = 3

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