# GATE2015-52

If $A = \begin{bmatrix} 4 & 2 \\ 1 & 3 \end{bmatrix}$, then $A^2+3A$ will be

1. $\begin{bmatrix} 30 & 20 \\ 10 & 20 \end{bmatrix} \\$
2. $\begin{bmatrix} 28 & 10 \\ 4 & 18 \end{bmatrix} \\$
3. $\begin{bmatrix} 31 & 13 \\ 7 & 21 \end{bmatrix} \\$
4. $\begin{bmatrix} 20 & 10 \\ 5 & 15 \end{bmatrix}$

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## Related questions

1
If $P=\begin{bmatrix}1&1\\2&2\end{bmatrix}, Q=\begin{bmatrix}2&1\\2&2\end{bmatrix}$ and $R=\begin{bmatrix}3&0\\1&3\end{bmatrix}$, which one of the following statements is $TRUE$? $PQ=PR$ $QR= RP$ $OP=RP$ $PO= OR$
2
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