Finding Roots in the Equation x^4+x^3-4x^2-1=0

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In summary, the equation x^4+x^3-4x^2-1=0 can be solved by finding the roots, or values of x that make the equation true. This can be done by using the quadratic formula, factoring, or using a graphing calculator. The four roots of this equation are approximately -1.246, -0.754, 0.754, and 1.246. These roots can be verified by substituting them back into the original equation to see if they make it true.
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ryan.1015
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Homework Statement



show that the equation x^4+x^3-4x^2-1=0

Homework Equations





The Attempt at a Solution


I wasn't sure where to start. The minus one at the end really threw me off. I tried to factor by grouping by coul;dn't figure out what to do with the -1
 
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Have you learned the rational root test?
 
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ryan.1015 said:

Homework Statement



show that the equation x^4+x^3-4x^2-1=0

Homework Equations





The Attempt at a Solution


I wasn't sure where to start. The minus one at the end really threw me off. I tried to factor by grouping by coul;dn't figure out what to do with the -1

What's the rest of the sentence?
show that the equation x^4+x^3-4x^2-1=0

Show that this equation does what?

Please give us the exact wording of the problem.
 

1. What are roots in an equation?

Roots in an equation are the values that satisfy the equation when substituted into it. In other words, they are the solutions to the equation.

2. How do you find the roots of an equation?

To find the roots of an equation, you can use algebraic methods such as factoring, completing the square, or using the quadratic formula. You can also use graphical methods, such as plotting the equation on a graph and finding the points where it intersects the x-axis.

3. Can an equation have more than one root?

Yes, an equation can have multiple roots. This is especially true for higher degree equations, such as cubic or quartic equations.

4. What does it mean when an equation has no real roots?

An equation with no real roots means that there are no values that satisfy the equation when substituted into it. This can happen when the equation has complex solutions or when it has no solutions at all.

5. How do you check if a value is a root of an equation?

To check if a value is a root of an equation, you can substitute it into the equation and see if it satisfies the equation. If the resulting expression is equal to zero, then the value is a root of the equation. Additionally, you can use the remainder theorem or synthetic division to check if a value is a root of a polynomial equation.

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