SOLUTION: find the rational zeros and then the other zeros for f(x)=x^3+27

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Question 729733: find the rational zeros and then the other zeros for f(x)=x^3+27
Answer by fcabanski(1391) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E3+%2B+27+=0


The rational root theorem states that if p/q is a zero of the function then p is a factor of the constant and q is a factor of the leading coefficient.


27 is the constant. Its factors are + or - 1, + or - 27, + or - 3 and + or -9.


1 is the leading coefficient. Its factors are + or -1.


You can make all the possible fractions p/q, then check each one to see if results in a 0 remainder when you divide the original function by it.


But you don't have to do that, because x%5E3+=+-27.


Take the cube root of both sides.


x+=+-3.