Algebra and Linear algebra (i. e. matrices). They should teach Linear algebra immediately after algebra. It's pretty easy and it's amazingly useful in all sorts of domains including machine learning.
代数和线性代数(比如：矩阵)，他们会在教完代数后立即教线性代数。这也简单，但这在相当多的领域非常有用，包括机器学习。
The right characteristic values of matrices on quaternion division algebra are discussed, and some corresponding results for complex matrices are generalized and improved.
讨论实四元数体上方阵的右特征值，并将域上矩阵的一些相应结果推广到实四元数体上。
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