Why Does Calculus Make f(x) Discontinuous?

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The function f(x) = (2x-2)/((x^2)+x-2) is discontinuous where the denominator equals zero, which occurs at specific x values. At these points of discontinuity, the limits of f(x) can be evaluated to determine their existence. For part C, the rational function g(x) = a/(b+x) must match f(x) wherever f(x) is defined, suggesting a relationship between the coefficients a and b. Factorization of both the numerator and denominator can simplify the analysis and provide insights into the values of a and b. Understanding these concepts is crucial for solving the problem effectively.
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Given the function f(x) by f(x) = (2x-2)/((x^2)+x-2)

A) For what values of 'x' is f(x) discontinuous?
B) At each point of discontinuity found in part A, determine whether f(x) has a limit and, if so, give the value of the limit.
C) A rational function g(x)= a/(b+x) is such that g(x)=f(x) wherever f(x) is defined. Find the values of 'a' and 'b'.

I think I figured out both part A and B, but part C is killing me. Any help would be great.
 
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ashleyk said:
Given the function f(x) by f(x) = (2x-2)/((x^2)+x-2)

A) For what values of 'x' is f(x) discontinuous?
B) At each point of discontinuity found in part A, determine whether f(x) has a limit and, if so, give the value of the limit.
C) A rational function g(x)= a/(b+x) is such that g(x)=f(x) wherever f(x) is defined. Find the values of 'a' and 'b'.

I think I figured out both part A and B, but part C is killing me. Any help would be great.
A function is discontinuous when the y value for a certain x value does not exist. In this case, it would be when the denominator equals zero. That should be pretty simple to figure out.
 
You must have skipped class not to get a).

Simon, from American Idol:

Like seriously, you skipped class and that shirt looks dirty awful.
 
For part C) have you tried factorising both numerator and denominator ? It should become fairly obvious then.
 
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