First, check that the table is in standard form, with x-values less than -5 on the left, and x-values greater than -5 on the right. It is already in standard form:
x approaching -5 from the left | x approaching -5 from the right | |||||||||||||||||||||
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This table gives us the following information:
As x approaches -5 from the left, g(x) approaches 23. In other words,
x-5 | g(x) = 23 |
Note The fact that you see the number 24 under x = -5 means that g(-5) = 24. That is, the value of g at -5 is 24. When taking the limit as x approaches -5, ignore the value of the function at x = -5. The limit is about what happens as x approaches -5, not what happens when x equals -5.
As x approaches -5 from the right, g(x) becomes very large, and is therefore approaching infinity. Therefore,
x-5 | g(x) = +∞. Some people say that it doesn't exist when this happens... |
Since the left- and right-hand limits do not agree there is no hope of the limx → -5 g(x) existing. In other words,
x-5 | g(x) does not exist. |
Finally, the value of the function at x = -5 is given by the table:
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