We first give an example to illustrate that the results in [12] concerning the boundedness of solutions of nonlinear oscillatory equations are not true. And then we obtain sufficient or necessary conditions for the bo...We first give an example to illustrate that the results in [12] concerning the boundedness of solutions of nonlinear oscillatory equations are not true. And then we obtain sufficient or necessary conditions for the boundedness of solutions of the nonlinear system of differential equations dx/dt=y~α, dy/dt=-f(x)y~βh(y)-g(x)k(y) without the usual signum conditions xg(x)】0 for all x≠0 and f(x)≥0 for all x∈R.展开更多
基金supported by the National Natural Science Foundation of China.
文摘We first give an example to illustrate that the results in [12] concerning the boundedness of solutions of nonlinear oscillatory equations are not true. And then we obtain sufficient or necessary conditions for the boundedness of solutions of the nonlinear system of differential equations dx/dt=y~α, dy/dt=-f(x)y~βh(y)-g(x)k(y) without the usual signum conditions xg(x)】0 for all x≠0 and f(x)≥0 for all x∈R.
