The value of the determinant \(\begin{vmatrix}3 & -4 & 5\\1 & 1 & -2\\2 & 3 & 1\end{vmatrix}\) is :
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → 46
Expanding along the first row, with the signs + − +:
\( \Delta = 3\begin{vmatrix}1 & -2\\3 & 1\end{vmatrix} - (-4)\begin{vmatrix}1 & -2\\2 & 1\end{vmatrix} + 5\begin{vmatrix}1 & 1\\2 & 3\end{vmatrix} \)
\( = 3(1 + 6) + 4(1 + 4) + 5(3 - 2) \)
\( = 21 + 20 + 5 \)
\( = 46 \)
NCERT (2026-27 edition):
Determinant
