This is an assignment problem I have. Can't seem to figure it out. It has two parts, one to prove that the function approaches 0 where y=mx and and one where the function approaches 0 from y=kx2... f(x,y) = (x3y)/(2x6+y2) I've attempted both parts and get stuck on what seems like the same issue. Basically I've substituted y=mx for y. Giving: Please assume that lim (x,mx)→(0,0) is at the beginning of these workings. lim f(x,mx) = x3(mx)/(2x6+(mx)2) lim f(x,mx) = mx4/[(x2(2x4+m2)] lim f(x,mx) = mx2/(2x4+m2) I suppose I could try L'Hopital at this point, but it doesn't seem to help I think the 3rd derivative leaves you with 0/0. Could I get some direction, please? Thanks prior!