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\title{Exercise 4.2.25}
\author{Emma Lindsley}
\date{October 22, 2019}

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If r is any rational number, then $3r^2-2r+4$ is rational.

Proof: Assume r is a rational number. Observe that $r=a\div{b}$ where $b\ne{0}$ and $a,b\in{\z}$.