Question 465762
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I moved your question to the correct category.


Rational functions are defined for all real numbers except those real numbers that would cause the denominator to equal zero.  Note that there must be at least one instance of a variable in the denominator in order for the expression to qualify as a rational expression.


Set the denominator expression equal to zero and solve the resulting equation.  All roots of this equation are excluded from the domain of the rational function.  In your case, since your denominator is a quadratic, and because the lead coefficient and the constant term have opposite signs, you have two real values that will satisfy the quadratic equation that results when you set the denominator equal to zero.  Those two numbers will cause the rational expression to be undefined.


John
*[tex \LARGE e^{i\pi} + 1 = 0]
My calculator said it, I believe it, that settles it
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