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Demo matrix of mathematical expressions

$A= \left(\begin{matrix} \phantom{.}\\\phantom{.}\\\phantom{.}\end{matrix} \right.$	interpreted as $\displaystyle{}$ Expected answer:interpreted as $\displaystyle{x_{1}}$	interpreted as $\displaystyle{}$ Expected answer:interpreted as $\displaystyle{y_{1}}$	$\left.\begin{matrix} \phantom{.}\\\phantom{.}\\\phantom{.}\end{matrix} \right)$
	interpreted as $\displaystyle{}$ Expected answer:interpreted as $\displaystyle{x_{2}}$	interpreted as $\displaystyle{}$ Expected answer:interpreted as $\displaystyle{y_{2}}$