Given a quadratic in x, find the cube of x

In summary, a quadratic equation is a polynomial equation with the highest power of the variable being 2. To find the cube of x in a quadratic equation, it must be rewritten in a specific form and the binomial theorem can be used. Finding the cube of x is important for solving the equation and identifying characteristics of its graph. It can be negative in complex root equations but is always positive for equations with real roots. There are formulas to find the cube of x, but they only work for equations with real roots.
  • #1
ter27
3
0
if $x^2 = x+3$ then $x^3 = ??$ Not sure about this would appreciate some help
 
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  • #2
Assuming that your question is the following:

If $x^2=x+3$, then find $x^3$

Here, we need to find what $x$ is, and to do so, we can apply the quadratic formula on $x^2-x-3=0$
 
  • #3
Rido12 said:
Assuming that your question is the following:

If $x^2=x+3$, then find $x^3$

Here, we need to find what $x$ is, and to do so, we can apply the quadratic formula on $x^2-x-3=0$

Thanks a lot have got it
 

FAQ: Given a quadratic in x, find the cube of x

What is a quadratic equation?

A quadratic equation is a type of polynomial equation in one variable (usually represented as x) where the highest power of the variable is 2. It is written in the form ax^2 + bx + c = 0, where a, b, and c are constants.

How do you find the cube of x in a quadratic equation?

To find the cube of x in a quadratic equation, you first need to rewrite the equation in the form (x + a)^3 = b, where a and b are constants. Then, you can use the binomial theorem to expand (x + a)^3 and simplify the equation to find the cube of x.

Why is finding the cube of x important in a quadratic equation?

Finding the cube of x can help us solve the quadratic equation and find the roots (or solutions) of the equation. It can also help us identify important characteristics of the graph of the quadratic equation, such as the vertex and the direction of the parabola.

Can the cube of x be negative in a quadratic equation?

Yes, the cube of x can be negative in a quadratic equation. This means that the quadratic equation has two complex (non-real) roots. However, if the equation has real roots, the cube of x will always be positive.

Are there any shortcuts or formulas to find the cube of x in a quadratic equation?

Yes, there are some shortcuts and formulas that can help you find the cube of x in a quadratic equation. For example, if the quadratic equation is in the form ax^2 + bx + c = 0, the cube of x can be found using the formula x = (-b ± √(b^2 - 4ac)) / 2a. It is important to note that this formula only works for equations with real roots.

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