THE ZEROS OF SOLUTIONS OF SOME DIFFERENTIAL INEQUALITIES

Let $x(t)$ satisty $$(p(t)x^{\prime}(t))^{\prime}+q(t)x^{{\alpha}}(t)+r(t)x^{{\beta}-1}x^{\prime}(t){\leq}0({\geq}0)$$. Then the zeros of $x(t)$ or $x^{\prime}(t)$ are simple.