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Calculate Determinant
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det(\left(\begin{matrix}1&-3&5\\2&-1&4\\1&1&0\end{matrix}\right))
Find the determinant of the matrix using the method of diagonals.
\left(\begin{matrix}1&-3&5&1&-3\\2&-1&4&2&-1\\1&1&0&1&1\end{matrix}\right)
Extend the original matrix by repeating the first two columns as the fourth and fifth columns.
-3\times 4+5\times 2=-2
Starting at the upper left entry, multiply down along the diagonals, and add the resulting products.
-5+4=-1
Starting at the lower left entry, multiply up along the diagonals, and add the resulting products.
-2-\left(-1\right)
Subtract the sum of the upward diagonal products from the sum of the downward diagonal products.
-1
Subtract -1 from -2.
det(\left(\begin{matrix}1&-3&5\\2&-1&4\\1&1&0\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}-1&4\\1&0\end{matrix}\right))-\left(-3det(\left(\begin{matrix}2&4\\1&0\end{matrix}\right))\right)+5det(\left(\begin{matrix}2&-1\\1&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.
-4-\left(-3\left(-4\right)\right)+5\left(2-\left(-1\right)\right)
For the 2\times 2 matrix \left(\begin{matrix}a&b\\c&d\end{matrix}\right), the determinant is ad-bc.
-4-\left(-3\left(-4\right)\right)+5\times 3
Simplify.
-1
Add the terms to obtain the final result.