SOLUTION: How do i find the determinant of A: A=[4, -7, 3, -2]?

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Question 176532: How do i find the determinant of A: A=[4, -7, 3, -2]?
Found 2 solutions by stanbon, jim_thompson5910:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
You don't; only a square matrix has a determinant.
Cheers,
Stan H.

Answer by jim_thompson5910(35256) About Me  (Show Source):
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


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:


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