#(x^3+x)/(x(x-1)#
#(x(x^2+1))/(x(x-1))#
#(cancelx(x^2+1))/(cancelx(x-1))#
#(x^2+1)/(x-1)=(x^2+1)*1/(x-1)#
#color(green)(lim_(x->a)f(x)*g(x)=lim_(x->a)f(x) *lim_(x->a)g(x)#
#lim_(x->1)(x^2+1)->(1+1)=2#
#lim_(x->1^+)(1/(x-1))=oo#
#lim_(x->1^-)(1/(x-1))=-oo#
#lim_(x->1^+)(1/(x-1))!=lim_(x->1^-)(1/(x-1))#
#:.#
#lim_(x->1)((x^3+x)/(x(x-1)))color(white)(888)#Undefined