2011/049) the value of a for which the equation

(a^2+4a+3) x^2 + (a^2-a-2) x + (a+1)a = 0 has more than 2 solutions is


ans:
if above is quadratic equation then it has 2 solutions and hence it must be identity so
a^2+4a + 3 = a(a+1) = 0
(a^2-a-2) = (a+1)(a-2) = 0
a(a+1) = 0

hence a+ 1 = 0 or a = -1