Interesting "real life" applications of serious theorems [closed]

applications big-list soft-question education

$\sqrt[n]{2}$ is not rational for $n\geq 3$

Proof: If $\sqrt[n]{2}=\frac{p}{q}$ then $q^n+q^n=p^n$ contradicting Fermat's last theorem.


In a cup of coffee, one molecule of coffee is in its original location, even though the contents are undergoing convection. This is the Brouwer fixed point theorem.

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