Suppose $f:\mathbb R^n\to\mathbb R$ is a smooth function and define $E_f := \{x\in\mathbb R^n\;|\;f(x)=0\text{ and }\nabla f(x)\ne 0\}$. Can we find $f$ such that $E_f$ has positive $n$-dimensional Lebesgue measure?
2026-02-23 01:17:10.1771809430
A Smooth Function with Peculiar Properties
183 Views Asked by Bumbble Comm https://math.techqa.club/user/bumbble-comm/detail AtRelated Questions in CALCULUS
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