If x = 1 is a common root of the equations ax2 + ax + 3 = 0 and x2 + x + b = 0, then ab =

Since x = 1 is root of equations, it will satisfy both the equations.

Putting x = 1 in ax2 + ax + 3 = 0


1a + a + 3 = 0


2a + 3 = 0


A = – 3/2


Putting x = 1 in x2 + x + b = 0


1 + 1 + b = 0


b = – 2



ab = 3

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