limx→0 3x2+27x2+21/x2is equal to
e-2
e2
e2/7
e3/7
limx→0 3x2+27x2+21/x2
=limx→0 1+3x2+27x2+2−11/x2
=limx→0 1+−4x27x2+21/x2=elimx→0−4x27x2+21x2=elimx→0 −47x2+2=e−2