Declaremathoperator
Add macros as \DeclareMathOperator? GED has for temf-math.sty:
\DeclareMathOperator{\grad}{grad} \DeclareMathOperator{\rot}{rot} \DeclareMathOperator{\curl}{curl} \let \div \relax \DeclareMathOperator{\div}{div} \DeclareMathOperator{\sign}{sgn} \DeclareMathOperator{\arsinh}{arsinh} \DeclareMathOperator{\arcosh}{arcosh} \DeclareMathOperator{\artanh}{artanh}