Question 116758This question is from textbook Intermediate Algebra
: Please help me solve this equation.
This question is from textbook Intermediate Algebra
Answer by solver91311(24713) (Show Source):
You can put this solution on YOUR website! This is not an equation. This is a polynomial expression. As it stands, there is no solution -- you can't 'solve' a polynomial expression.
So, let's presume that you actually meant to say 'Please solve: .
The first thing you can do is factor out of the left side leaving you with:
That gives us two of the five roots directly, namely and
From here on it gets mighty ugly. Looking at a graph of the cubic factor, we can see that we have one real root, slightly smaller than and a conjugate pair of complex roots.
My recommendation, to the extent that your instructor will be satisfied with a reasonable approximation, is to go to a website that has a general cubic equation solver. When you use such a thing, just be sure to remember that the c coefficient in has a zero value in this problem.
There is another possibility that occurred to me -- you may have a typo in your polynomial. If you actually meant , then becomes:
and we are left with a much easier to handle quadratic.
Solved by pluggable solver: SOLVE quadratic equation with variable |
Quadratic equation (in our case ) has the following solutons:

For these solutions to exist, the discriminant should not be a negative number.
First, we need to compute the discriminant : .
The discriminant -467 is less than zero. That means that there are no solutions among real numbers.
If you are a student of advanced school algebra and are aware about imaginary numbers, read on.
In the field of imaginary numbers, the square root of -467 is + or - .
The solution is 
Here's your graph:
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Not nearly as messy, even though the roots are complex.
Hope this helps.
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