The extremal formula of binary quadratic functions is studied by using method of undetermined coefficients, substitution method and method of completing the square.
用特定系数法、换元法、配方法探求二元二次函数的极值公式。
Taking one-dimensional diffusing equation as the object of study, a method of undetermined coefficients was given. Then gave two examples and analyzed their stability and truncation error.
针对一维扩散方程，给出一种新型差分格式的待定系数法，并以两种新型差分格式为例进行稳定性和截断误差分析。
The author describes the approximation and method of undetermined coefficients used in the practice of flowrate measurement.
介绍了笔者在流量计量实践中所用过的逼近法和待定系数法。
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