∵y=lim(x->∞){[(x^2n-1)/(x^2n+1)]x}∴当│x│1时,y=x∵lim(x->1+)y=lim(x->1+)(x)=1lim(x->1-)y=lim(x->1-)(-x)=-1∴lim(x->1+)y≠lim(x->1-)y,即x=1是第一类间断点∵lim(x->-1+)y=lim(x->-1+)(-x)=1lim(x->-1-)y=lim(x->-1-)(x)=-1∴lim(x->-1+)y≠lim(x->-1-)y,即x=-1是第一类间断点