Is the function given by f(x)= x+1/x^2-8x+12 continuous at x=2? why or why not?

1 Answer
Oct 21, 2017

See the explanation below

Explanation:

We have to look for the existence of a limit

#lim_(x->2)f(x)=lim_(x->2)(x+1)/(x^2-8x+12)=lim_(x->2)3/0=+oo#

So, there is a discontinuity at #x=2#

We look for the following limits

Limit on the left

#lim_(x->2^-)f(x)=lim_(x->2^-)(x+1)/(x^2-8x+12)=lim_(x->2)3/0^+=+oo#

Limit on the right

#lim_(x->2^+)f(x)=lim_(x->2^+)(x+1)/(x^2-8x+12)=lim_(x->2)3/0^-=-oo#

As #lim_(x->2^-)f(x)!=lim_(x->2^+)f(x)#, we conclude that #f(x)# is not

continuous at #x=2#