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In the first group of examples u is an unknown function of x, and c and ω are constants that are supposed to be known. Two broad classifications of both ordinary and partial differential equations consist of distinguishing between linear and nonlinear differential equations, and between homogeneous differential equations and heterogeneous ones.

In the first group of examples u is an unknown function of x, and c and ω are constants that are supposed to be known. Two broad classifications of both ordinary and partial differential equations consist of distinguishing between linear and nonlinear differential equations, and between homogeneous differential equations and heterogeneous ones.

在第一组例子中，待求解的''u''是''x''的函数，''c''和''ω''是应该已知的常数。常微分方程和偏微分方程这两种广义分类下还要区分微分方程的线性和非线性，以及区分微分方程的齐次和非齐次。

在第一组示例中，待求解的''u''是''x''的函数，''c''和''ω''是应该已知的常数。常微分方程和偏微分方程这两种广义分类下还要区分微分方程的线性和非线性，以及区分微分方程的齐次和非齐次。