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来源：雅诚德英语网
The motion of spherical pendulum in z-direction is described by nonlinear oscillation equation.
用非线性振动方程描述了球摆在 z 方向上的运动。
The motion of spherical pendulum in z-direction is described by nonlinear oscillation equation.
用非线性振动方程描述了球摆在 z 方向上的运动。