Assume we have two asymptotically non$-$negative functions f$1($x$),$ f$2($x$).$ disprove

$($a$)$ max$($f$1($x$),$ f$2($x$))=\backslash$theta $($f$1($x$)+$ f$2($x$)).(5$ pt$)$

$($b$)$ f$1($x$)+$ f$2($x$)=\backslash$theta $($min$($f$1($x$),$ f$2($x$))).$