LittleNew wrote:
Is the problem that it doesn't look right in LyX itself or in the LaTeX output? I don't think it will look any different in LyX. But it should look right in the output.Hello I'm new to Lyx. I wanted to add a "\arccot" self-defined function in my document, and I followed the help's instruction to add "\DeclareMathOperator{\arccot}{arccot}" in "Document->settings...->LaTeX Preamble", but after I did it, nothing happened. When I typed "\arccot", it still does not act like "\sin" or "\arctan". It does't turn to upright font. With my research getting deeper, I found that the hlep document "Math.lyx" in my LYX, also suffered from the similar failure. In this document, the examples which should've demonstrated the usage of "\DeclareMathOperator" doesn't work too, including "\\DeclareMathOperator*{\Lozenge}{\blacklozenge}" and "\DeclareMathOperator{\sgn}{sgn}".
rh
