Let P be a continuous function on ℝ and W be the Wronskian of two linearly independent solutions y1 and y2 of the ODE:
\(\rm \frac{d^{2} y}{d x^{2}}+\left(1+x^{2}\right) \frac{d y}{d x}\) + P(x) y = 0, x ∈ ℝ.
Let W(1) = a, W(2) = b and W(3) = c, then
1
a < 0 and b > 0
2
a < b < c or a > b > c
3
\(\rm \frac{a}{|a|}=\frac{b}{|b|}=-\frac{c}{|c|}\)
4
0 < a < b and b > c > 0