Given that the parabola y = 2x2 + 6x + m intersects the X axis at points a and B, and ab = 2, then M=______ ．

Given that the parabola y = 2x2 + 6x + m intersects the X axis at points a and B, and ab = 2, then M=______ ．

Let y = 0, then 2x2 + 6x + M = 0. Let a and B have two roots of the equation. Then a + B = - 3, ab = m2. So | A-B | = (a + b) 2 − 4AB = 2, that is 9-2m = 4, the solution is m = 52

X square - 6x + 4 > 0

　　x^2-6x+4>0
x^2--6x+9--5>0
(x--3)^2--5>0
(X -- 3 + radical 5) (X -- 3 -- radical 5) > 0
So the solution of the original inequality is:
X > 3 + radical 5, or X

The square of X + 6x-4 = 0 to solve the equation

x^2+6x+9=13
(x+3)^2=13
x= -3+-v13