Finding Polynomials with Integer Coefficients & \sqrt(2) + i Zero

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SUMMARY

The discussion focuses on finding a polynomial with integer coefficients for which the complex number \(\sqrt{2} + i\) is a zero. The proposed solution involves expanding the expression \((\sqrt{2} + i)^2\) and \((\sqrt{2} + i)^4\) to derive the polynomial. The initial attempt yielded the expression \(x^2 - 2\sqrt{2}x + 2 - i\), which is not a valid polynomial with integer coefficients due to the presence of \(\sqrt{2}\) and \(i\). The correct approach requires ensuring that all coefficients are integers.

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Homework Statement



Find a polynomial with integer coefficient for which \sqrt(2) + i is a zero.

Homework Equations



The Attempt at a Solution



I'm not sure where to really start with this one. It is on my review sheet, and I can't remember how to do it. Could someone give me a hand?
 
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duki said:

Homework Statement



Find a polynomial with integer coefficient for which \sqrt(2) + i is a zero.

Homework Equations



The Attempt at a Solution



I'm not sure where to really start with this one. It is on my review sheet, and I can't remember how to do it. Could someone give me a hand?

consider (sqrt(2)+i)2...what are you left with after expanding and simplifying?
how about (sqrt(2)+i)4?
 
Ok, as an answer I got:

x^2 - 2 \sqrt{2}x + 2 - i
Does that look right?
 
Latex isn't working, so I got

x^2 - 2sqrt(2)x + 2 - i
 

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