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I was looking for a way to put 'des' over the equals sign in latex and stumbled upon this symbol

$\circeq$

What are mathematicians using it for?

Hennadii Madan
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1 Answers1

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A quick Google search shows a few uses of $\circeq$ to represent a binary relation. Examples:

If $\Sigma, \Delta$ are sets of sentences, say that $\Sigma \circeq \Delta$ iff they have the same models.

and

Let $\circeq$ be the relation on the set $P(\mathbb R)$ of all polynomials with real coefficients defined by $f \circeq g$ iff $f$ and $g$ have a root in common.

The character is also known as "ring equal to".

grand_chat
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