Determinant Equality Explained without Evaluation | Boas 3rd Ed. HW Question 7

AI Thread Summary
The discussion focuses on demonstrating the equality of two determinants from Boas' 3rd edition without directly evaluating them. Participants suggest manipulating the rows and columns of the determinants, including multiplying rows by constants and performing column interchanges while tracking sign changes. There is an emphasis on using proper notation for determinants, as vertical lines are preferred over brackets. One user expresses difficulty with LaTeX formatting, indicating a need for clearer communication in mathematical notation. The conversation encourages collaborative problem-solving and offers assistance for further questions.
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Homework Statement



Show without evaluating the determinant the equality.

Homework Equations

<br /> <br /> \left(<br /> \begin{array}{ccc}<br /> 1 &amp; a &amp; bc \\<br /> 1 &amp; b &amp; ac \\<br /> 1 &amp; c &amp; ab<br /> \end{array}<br /> \right)<br /> <br />

=

<br /> <br /> \left(<br /> \begin{array}{ccc}<br /> 1 &amp; a &amp; a^2 \\<br /> 1 &amp; b &amp; b^2 \\<br /> 1 &amp; c &amp; c^2<br /> \end{array}<br /> \right)<br /> <br />

The Attempt at a Solution



I tried the facts of determinants - I did column 3 plus column 2. I can't see it. This is actually a Question on Boas 3rd Ed. Chapter 3 Section 3 No. 7.
 
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(The brackets that you are using is generally used for matrices; for a determinant, vertical lines are used to enclose it.)

Multiply the first row by 'a' and get 1/a outside. The 1st row becomes |a a^2 abc|. Now think what you can multiply the 2nd and 3rd rows with.

After that, take out something common from a column.

Then interchange columns or do a cyclic permutation on the columns, keeping track of the sign of the determinant. You will get the answer.

For any help, don't hesitate to ask.
 
Shooting Star said:
(The brackets that you are using is generally used for matrices; for a determinant, vertical lines are used to enclose it.)

Multiply the first row by 'a' and get 1/a outside. The 1st row becomes |a a^2 abc|. Now think what you can multiply the 2nd and 3rd rows with.

After that, take out something common from a column.

Then interchange columns or do a cyclic permutation on the columns, keeping track of the sign of the determinant. You will get the answer.

For any help, don't hesitate to ask.

Yeah, I actually just copied and pasted that from somewhere here that I searched for, sorry, I don't know LATEX. Thanks, I will try your suggestion.
 
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