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November 21st, 2009, 11:16 AM   #1
 
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Discontinuous limits

If f(x) = a-x^2 if x<-1, and x-b if x>-1
How do I figure out the values of a and b ?

Is it any values that make the f(x) value different when x is approached from the left or the right?
bebesofly is offline  
 
November 21st, 2009, 04:21 PM   #2
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Re: Discontinuous limits

Quote:
Originally Posted by bebesofly
If f(x) = a-x^2 if x<-1, and x-b if x>-1
How do I figure out the values of a and b ?

Is it any values that make the f(x) value different when x is approached from the left or the right?
Your question is very unclear. At x=-1 you have from the left a-1 and from the right -1-b. For continuity a=-b. Without any more information that is as far as you can get.
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November 21st, 2009, 07:14 PM   #3
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Re: Discontinuous limits

Hello, bebesofly!

As mathman pointed out, the question is not clearly stated.
We must guess the intent of the problem.


Quote:


How do I figure out the values of and ?

Is it any values that make the value different when approaches -1 from the left or the right?

[color=blue]I assume you're seeking values of a and b which make the function discontinuous at x = -1.[/color]

If the function is continuous at , then has the same value "from both sides."

From the left:[color=beige] .[/color]

From the right:[color=beige] .[/color]

If they are equal:[color=beige] .[/color]




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