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autonum is often preferred over mathtools ’ showonlyrefs because autonum works with more environments and handles \label placement more robustly. \documentclassarticle \usepackageamsmath \usepackage[colorlinks]hyperref \usepackagecleveref \usepackageautonum \begindocument
\beginequation g(x) = \sqrtx \labeleq:root \endequation autonum.info
\usepackageautonum \documentclassarticle \usepackageamsmath \usepackageautonum \begindocument
As Einstein said, see \eqrefeq:einstein. \enddocument autonum is often preferred over mathtools ’
\beginalign x &= y + z \labeleq:first \ a &= b - c \labeleq:second \endalign
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On first compile, both equations may appear numbered. On the , autonum reads the .aux file, sees that eq:einstein is referenced, and keeps its number. The Pythagorean equation remains unreferenced, so its number disappears. 3.3 With align and cleveref \documentclassarticle \usepackageamsmath, cleveref \usepackageautonum \begindocument
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