(adsbygoogle = window.adsbygoogle || []).push({}); Number theory--product of squares

1. The problem statement, all variables and given/known data

Suppose a and b are two integers, which can each be written as the sum of

two squares. Prove that ab can be expressed as the sum of two squares.

2. Relevant equations

3. The attempt at a solution

a=c[itex]^{2}[/itex]+d[itex]^{2}[/itex]

b=x[itex]^{2}[/itex]+y[itex]^{2}[/itex]

I'm not exactly sure how to approach this proof.

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# Homework Help: Number theory-product of squares

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