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If A and B are 4x4 matrices, det(A) = -4, det(B) = 3, then (b) det(3A) = ????,

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bobboooooooo | Student | eNoter

Posted April 28, 2013 at 1:18 AM via web

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If A and B are 4x4 matrices, det(A) = -4, det(B) = 3, then

(b) det(3A) = ????,

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tiburtius | High School Teacher | (Level 3) Associate Educator

Posted April 28, 2013 at 6:05 AM (Answer #1)

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One property of determinants says for `nxxn` matrix `A` and some scalar `c` the following holds

`det(c cdot A)=c^ndet(A)`

Hence we have

`det(3A)=3^4det(A)=81cdot(-4)=-324` <-- Solution

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