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August19,2021
$$ |kA| = k^n|A| $$ $$ (kA)^T = kA^T $$ $$ (A+B)^T = A^T + B^T $$ $$ AA^\*=A^\*A $$ $$ A^\* = |A|A^{-1} $$ $$ AA^\*...
球面坐标系 $$ \begin{cases} x = r\sin\phi\cos\theta \\ y = r\sin\phi\sin\theta \\ z = r\cos\phi \end{cases} $$ ...