If the real numbers a and B satisfy A2 + B2 ≤ 1, then the probability of the equation x2-ax + 34b2 = 0 with real roots is zero______ ．

If the real numbers a and B satisfy A2 + B2 ≤ 1, then the probability of the equation x2-ax + 34b2 = 0 with real roots is zero______ ．

For the equation x2-ax + 34b2 = 0 of X has real roots, then the discriminant △ = A2-4 × 34b2 = a2-3b2 ≥ 0, that is, (a-3b) (a + 3b) ≥ 0, make the plane region corresponding to the inequality system as shown in the figure: then the slope of a-3b = 0 is k = 33, the corresponding inclination angle is 30 °, the slope of a + 3B = 0 is k = - 33, the corresponding inclination angle is 150 °