Question

*Demonstrati egalitatea : $\left[\begin{array}{ccc}2&4\\1&3&\\\end{array}\right]$-3$\left[\begin{array}{ccc}5&2\\2&1&\\\end{array}\right]$=$\left[\begin{array}{ccc}0&1&\\1&0&\\\end{array}\right]$

*Fie matricele A=$\left(\begin{array}{ccc}3&-2&\\4&-1&\\\end{array}\right)$ si B=3A.
Demonstrati ca det(B)=9det(A).

Answer 1

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