On the other hand, it also derives the covariance propagation formula of non-linear function containing quadratic term in matrix form using the matrix theory etc.

另一方面又利用矩阵理论等推导出含有二次项的非线性函数的协方差传播公式的矩阵形式。

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Method of completing square is often used when transforming a quadratic form into a normal one, whose process is equivalent to making the relevant matrix contract diagonal.

二次型化标准形常采用配方法，而二次型化标准形等价于它的矩阵合同对角化，文中利用初等矩阵和初等变换之间的关系。

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The formulas to calculate the variance of a quadratic form with the matrix composed of submatrices are given in this paper.

给出了由子矩阵组成的分块矩阵时，随机变量二次型的方差、协方差的计算公式。

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