Proving a formula for the determiante in a special matrix

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Homework Statement



Let a1, a2 are real numbers, where n > 1 show that: determinant of:

| 1 a1 a21 ... ... an-11 |
| 1 a2 a22 ... ... an-12 |
:
:
| 1 an a2n ... ... an-1n |


= \prod (aj - ai)
1\leqi<j<n

Homework Equations


if you row reduce a matrix the determinate is the product of the leading diagonal(previous question was finding determinate of matrices by row reducing them)

The Attempt at a Solution


tried using induction but get stuck very quickly.
i got RHS =
= \Pi0<i<j<n (aj - ai) \Pi0<k<n (an - ak)
 
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rosh300 said:
show that: determinant of …
= \prod (aj - ai)
1\leqi<j<n

i got RHS =
= \Pi0<i<j<n (aj - ai) \Pi0<k<n (an - ak)

Hi rosh300! :smile:

But that's the answer, isn't it?

The first part is all non-identical pairs up to n-1, and the second part is all non-identical pairs of which the higher is n.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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