Quasihyperbolic

We prove that for a bounded domain #92;Omega#92;subset#92;mathbbRⁿ which is Gromov hyperbolic with respect to the quasihyperbolic metric, especially when #92;Omega is a finitely connected planar domain, the Sobolev space W#123;1,#92;,#92;infty#125;(#92;Omega) is dense in W#123;1,#92;,p#125;(#92;Omega) for any 1#92;leplt;#92;infty.