工程问题中常用微分方程的形式建立数学模型，所以微分方程求解很有意义。本程序用Euler、改进Euler和经典公式对这类方程进行求解-Engineering problems commonly used in the form of differential equations to establish the mathematical model, it makes sense for solving differential equations. This procedure used Euler, improved Euler and the classical formula of such equations to solve
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