SOLUTION: x^4-7x^3+18x-126=0

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Question 180460: x^4-7x^3+18x-126=0
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
+graph%28+300%2C+300%2C+-5%2C+10%2C+-10%2C+10%2C+x%5E4-7x%5E3%2B18x-126%29+
Looks like x=7 is a root.
7%5E4-7%287%29%5E3%2B18%287%29-126=0
126-126=0
You can iterate to find another root is between x=-2 and x=-3 at about x=-2.62074.
We can do a long division to find the exact value.
%28x%5E4-7x%5E3%2B18x-126%29%2F%28x-7%29=x%5E3%2B18
x%5E3=-18
x=-18%5E%281%2F3%29
or approximately,
x=-2.62074
Is that what you were looking for??