How do you find the determinant of #|(-6,5),(0,-8)|#?

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Answer 1 · 2016-12-13T18:45:10

#abs((-6,5),(0,-8)) = 48#

The determinant of a #2xx2# square matrix is given by the formula:

#abs((a,b),(c,d)) = ad-bc#

So in our example:

#abs((-6,5),(0,-8)) = (-6)(-8)-(5)(0) = 48-0 = 48#

More generally, if #M# is any upper or lower triangular matrix, then its determinant is the product of the main diagonal.

So we could have just written:

#abs((-6,5),(0,-8)) = (-6)(-8) = 48#