Question 801636
y^3(y-4) / y^2(y-4) 
It says for each rational function, find all numbers that aren't in the domain. 
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The denominator cannot be zero::
Solve y^2(y-4) = 0
y = 0 or y = 4
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Domain: All Real Numbers except y = 0 and y = 4
{y | -oo< y < 0, 0< y < 4, 4< y <+oo}
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Cheers,
Stan H.
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