What is the limit?

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1 Answer
Feb 6, 2018

#lim_(x->3)(f(x)-f(3))/(x-3)=0#

Explanation:

#f(3)=3^2-6(3)+3=-6#

#f(x)-f(3)=x^2-6x+3-(-6)=x^2-6x+9#

We now have #lim_(x->3)(x^2-6x+9)/(x-3)#

Using L'Hopital's rule, we know that if #f(x)/g(x)=0/0oroo/oo#, then #lim_(x->a)f(x)/g(x)=(f'(a))/(g'(a))#

In this case we have #lim_(x->3)(x^2-6x+9)/(x-3)=(2(3)-6)/(1)=(6-6)/1=0/1=0#