document.write( "Question 176532: How do i find the determinant of A: A=[4, -7, 3, -2]? \n" ); document.write( "

Algebra.Com's Answer #131630 by jim_thompson5910(35256) $\"\"$ $\"About$

You can put this solution on YOUR website!
I'm assuming that the matrix is really $\"A=%28matrix%282%2C2%2C4%2C+-7%2C+3%2C+-2%29%29\"$ \r
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Solved by pluggable solver: Finding the Determinant of a 2x2 Matrix

If you have the general 2x2 matrix:

$\"%28matrix%282%2C2%2Ca%2Cb%2Cc%2Cd%29%29\"$

the determinant is: $\"D=a%2Ad-c%2Ab\"$

So this means that

$\"abs%28matrix%282%2C2%2Ca%2Cb%2Cc%2Cd%29%29=a%2Ad-c%2Ab\"$

Note: the vertical bars denote a determinant.

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So in this case the determinant of $\"%28matrix%282%2C2%2C4%2C-7%2C3%2C-2%29%29\"$ is:

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$\"abs%28matrix%282%2C2%2C4%2C-7%2C3%2C-2%29%29=%284%29%28-2%29-%283%29%28-7%29=-8--21=13\"$

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Answer:

So $\"abs%28matrix%282%2C2%2C4%2C-7%2C3%2C-2%29%29=13\"$ which means that the determinant of the matrix $\"%28matrix%282%2C2%2C4%2C-7%2C3%2C-2%29%29\"$ is 13

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