Question

Find the value of the determinant
\[\begin{bmatrix}4200 & 4201 \\ 4205 & 4203\end{bmatrix}\]

Answer 1

\[\text{ Let }\Delta = \begin{vmatrix} 4200 & 4201\\4202 & 4203 \end{vmatrix}\] 
\[ \Delta = \begin{vmatrix} 4200 & 1\\4202 & 1 \end{vmatrix} \left[\text{ Applying }C_2 \to C_2 - C_1 \right]\] 
\[ = 4200 - 4202 \] 
\[ = - 2\]