Question 263968
find all the numbers for which the rational expression is undefined. 
s^3-9s/s^2-64 
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Undefined when the denominator is zero.
Solve s^2-64 = 0
Factor:
(s-8)(s+8) = 0
s = 8 or s = -8
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Undefined if s = 8 or s= -8
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Cheers,
Stan H.