Question 459562
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A rational expression is defined for all values of the variable except those values that would make the denominator be equal to zero.  Find the zeros of the denominator polynomial and exclude those values.  Hint: The denominator is the difference of two squares so it factors easily.

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