SOLUTION: I need all the roots and zeros to these problems x^3+3x^2-5x-4=0 x^4-2x^3-7x^2+18x-18+=0

Question 107254: I need all the roots and zeros to these problems
x^3+3x^2-5x-4=0
x^4-2x^3-7x^2+18x-18+=0
Answer by Fombitz(32388) (Show Source): You can put this solution on YOUR website!
First example.
A quick graph of the function shows that x=-4 looks like a root of the equation.

You can then find the polynomial g(x) such that

where and

Compare that to your original equation.
and you see that
1.
2.
3.
4.
From 1 and 2,

From 4,

You can then find the roots of g(x) using the quadratic equation.

The roots of g(x) are then

or approximately, x=-0.62 and x=1.62
Second example.
A quick graph of the function shows that x=-3 and x=3 look like roots of the equation.

So then you can rewrite your equation to look like.

where

Follow the first example above to find a,b,and c.
Post another question if you get stuck.
Good luck.
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