$----161718$The derivative of f$($x$)=(3)/($x$)+(4)/($x$^(3))$f$^(\text{'})($x$)=-(3)/($x$^($x$))-(8)/($x$^($x$))$f$^(\text{'})($x$)=3+(4)/($x$)$f$^(\text{'})($x$)=-3-8$xIf in not posistit so determine