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Calculate Determinant
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det(\left(\begin{matrix}1&-2&2\\3&0&1\\4&-1&3\end{matrix}\right))
Find the determinant of the matrix using the method of diagonals.
\left(\begin{matrix}1&-2&2&1&-2\\3&0&1&3&0\\4&-1&3&4&-1\end{matrix}\right)
Extend the original matrix by repeating the first two columns as the fourth and fifth columns.
-2\times 4+2\times 3\left(-1\right)=-14
Starting at the upper left entry, multiply down along the diagonals, and add the resulting products.
-1+3\times 3\left(-2\right)=-19
Starting at the lower left entry, multiply up along the diagonals, and add the resulting products.
-14-\left(-19\right)
Subtract the sum of the upward diagonal products from the sum of the downward diagonal products.
5
Subtract -19 from -14.
det(\left(\begin{matrix}1&-2&2\\3&0&1\\4&-1&3\end{matrix}\right))
Find the determinant of the matrix using the method of expansion by minors (also known as expansion by cofactors).
det(\left(\begin{matrix}0&1\\-1&3\end{matrix}\right))-\left(-2det(\left(\begin{matrix}3&1\\4&3\end{matrix}\right))\right)+2det(\left(\begin{matrix}3&0\\4&-1\end{matrix}\right))
To expand by minors, multiply each element of the first row by its minor, which is the determinant of the 2\times 2 matrix created by deleting the row and column containing that element, then multiply by the element's position sign.
-\left(-1\right)-\left(-2\left(3\times 3-4\right)\right)+2\times 3\left(-1\right)
For the 2\times 2 matrix \left(\begin{matrix}a&b\\c&d\end{matrix}\right), the determinant is ad-bc.
1-\left(-2\times 5\right)+2\left(-3\right)
Simplify.
5
Add the terms to obtain the final result.