What is the limit of #(3x^2) / (x^2+2x)# as x approaches infinity?

2 Answers
Mar 3, 2017

#3#

Explanation:

divide terms on numerator/denominator by the highest power of x, that is #x^2#

#((3x^2)/x^2)/(x^2/x^2+(2x)/x^2)=3/(1+2/x)#

#rArrlim_(xtooo)(3x^2)/(x^2+2x)#

#=lim_(xtooo)3/(1+2/x)#

#=3/(1+0)#

#=3#

Mar 3, 2017

# lim_(x->oo) (3x^2)/(x^2+2x) =3#

Explanation:

We can manipulate the limit as follows

# lim_(x->oo) (3x^2)/(x^2+2x) = lim_(x->oo) (3x^2)/(x^2+2x) *(1/x^2)/(1/x^2)#
# " "= lim_(x->oo) (3)/(1+2/x) #
# " "= 3 #

As #2/x rarr 0# as #x rarr oo#