If $$\alpha$$, $$\beta$$ be the roots of $${x^2} - a(x - 1) + b = 0$$, then the value of $${1 \over {{\alpha ^2} - a\alpha }} + {1 \over {{\beta ^2} - a\beta }} + {2 \over {a + b}}$$ is

The sum of all real roots of the equation $$|x - 2{|^2} + |x - 2| - 2 = 0$$ is

The quadratic equation whose roots are three times the roots of $$3a{x^2} + 3bx + c = 0$$ is

If a, b, c are real, then both the roots of the equation $$(x - b)(x - c) + (x - c)(x - a) + (x - a)(x - b) = 0$$ are always