(Solved): Short matrix algebra review. (a) Compute the following matrix product. 3231122121 ...

Short matrix algebra review. (a) Compute the following matrix product. $$\left[\begin{array}{lll}3& 1& 2\\ 2& 1& 1\\ 3& 2& 2\end{array}\right]\left[\begin{array}{r}1\\ ?1\\ 2\end{array}\right]$$ (b) Compute the following matrix product. $$\left[\begin{array}{ll}3& 1\\ 2& 1\end{array}\right]\left[\begin{array}{rr}1& 1\\ ?3& ?1\end{array}\right]$$ (c) Given the equations $$2a+3b=?1\text{ and }a?b=2,$$ set up the corresponding $$2\times 2$$ matrix system. Then solve the system for $$a$$ and $$b$$ using the matrix inverse.