Matrix, Find determinant using properties of Det.

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am_knightmare
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Homework Statement


1 1 1
a b c = (b-a)(c-a)(c-b)
a^2 b^2 c^2
(above is a 3x3 matrix equaling to a equation)
question:"Show by applying property of the determinant"

Homework Equations


N/A

The Attempt at a Solution


read through the whole chapter of determinants, there were no similar problems. read it the second time focusing on properties, no simimlar properties, Please help.
 
Start by subtracting the first column from the second and third columns. Then think about an expansion by minors.
 
Just solved it. thanks for the reply though.
1 1 1
a b c
a^2 b^2 c^2
becomes
1 0 0
a b-a c-a
a^2 (b^2-a^2) (c^2-a^2)
then becomes
(b-a)(c-a) times
1 0 0
a 1 1
a^2 b-a c-a
then
1 0 0
a 1 0
a^2 b-a c-b
det= 1 x 1 x(c-b) ( c-a) (b-a)
 
am_knightmare said:
Just solved it. thanks for the reply though.
1 1 1
a b c
a^2 b^2 c^2
becomes
1 0 0
a b-a c-a
a^2 (b^2-a^2) (c^2-a^2)
then becomes
(b-a)(c-a) times
1 0 0
a 1 1
a^2 b-a c-a
then
1 0 0
a 1 0
a^2 b-a c-b
det= 1 x 1 x(c-b) ( c-a) (b-a)

Yup. That'll do it.