Scalar Multiplication

Find $3\times \left(\begin{array}{cc}1& 2\\ 3& 4\end{array}\right)$.

• 1Multiply every element by $3$: $1\times 3=3$, $2\times 3=6$, $3\times 3=9$, $4\times 3=12$

Answer: $\left(\begin{array}{cc}3& 6\\ 9& 12\end{array}\right)$

Find $-2\times \left(\begin{array}{cc}2& -1\\ 0& 5\end{array}\right)$.

• 1Multiply every element by $-2$: $2\times (-2)=-4$, $-1\times (-2)=2$, $0\times (-2)=0$, $5\times (-2)=-10$

Answer: $\left(\begin{array}{cc}-4& 2\\ 0& -10\end{array}\right)$