I need to use trebuchet font. But bold and italic don't work.
\renewcommand{\rmdefault}{trebuchet}
What I need to work?
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Trebuchetis installed on your computer, you probably need to run your tex file through either XeLaTeX or LuaLaTeX, using commands\usepackage{fontspec}andsetmainfont{Trebuchet MS}(on a Mac system, not sure what the font's name is on a Windows system or other OS). – Mico Oct 10 '12 at 4:18