"We can easily check that the limit as x approaches 3 from the right and from the left is equal to 4. Hence, the limit as x approaches 3 exists, and therefore the function has a removable discontinuity at x = 3. If we define k(3) = 4 instead of k(3) = 1 then the function in fact will be continuous on the real line."
I think from the left is eqal to 6 not to 4. Thanks.
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