Need help with this

FrontS

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Mar 17, 2019
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"m" is a root of the following equation :
x^2 + 2x - 4 = 0

What is (m-1)(m-2)(m+3)(m+4) equal to?
 

MarkFL

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Hello, and welcome to FMH! :)

Hint: Try arranging the quartic expression in \(m\) as a quadratic in \(m^2+2m\). :)
 

Jomo

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Alternatively, you can solve x^2 + 2x - 4 = 0 and call the solution(s) m and then compute (m-1)(m-2)(m+3)(m+4)
 

topsquark

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Aug 27, 2012
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Hello, and welcome to FMH! :)

Hint: Try arranging the quartic expression in \(m\) as a quadratic in \(m^2+2m\). :)
Interesting idea. How did you come up with this?

-Dan
 

MarkFL

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Interesting idea. How did you come up with this?

-Dan
I put the expression "(m-1)(m-2)(m+3)(m+4) " into W|A to see what I got, and one form it gave was a quadratic in \(m^2+2m\). This makes answering the question straightforward, and without having to know the value of \(m\), which for problems like this, I think is a general desire by the authors of these problems.
 
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