1.

\left| \begin{array} { l l l } { x } & { 1 } & { 1 } \\ { 1 } & { x } & { 1 } \\ { 1 } & { 1 } & { x } \end{array} \right| = ( x + 2 ) ( x - 1 ) ^ { 2 }

Answer»


Discussion

No Comment Found