Question 762559
What is the value of the determinant? 
|3 6 8|
|2 4 0|
|3 6 8|
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Use minors
Using the top row:
Det = 3*minor1 - 6*minor2 + 8*minor3
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For minors, cross off the row & column
minor1 is
|4 0|
|6 8|
etc
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--> 3*(4*8 - 6*0) = 96 for minor1
--> 6*(2*8 - 3*0) = -96 for minor 2
--> 8*(2*6 - 3*4) = 0 for minor3
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Adding those --> Det = 0
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