How can -x^3 + 27 be factored?

In summary, the conversation is about factoring the expression -x^3 + 27. The person asking for help is struggling with the negative exponent and is given two formulas to try. They are able to use the second formula to solve the problem with the help of the physics forum.
  • #1
Draggu
102
0

Homework Statement


factor -x^3 + 27


Homework Equations





The Attempt at a Solution



Nothing, I have no idea how to factor it.
 
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  • #2
Here are a couple of formulas for you:
a3 + b3 = (a + b)(a2 - ab + b2)
a3 - b3 = (a - b)(a2 + ab + b2)
 
  • #3
Mark44 said:
Here are a couple of formulas for you:
a3 + b3 = (a + b)(a2 - ab + b2)
a3 - b3 = (a - b)(a2 + ab + b2)

I tried those. My main problem is the -x^3.
 
  • #4
You've got 3^3-x^3. That fits the second formula Mark44 gave you.
 
  • #5
2 seconds on physics forum and I found what I'm after. Thanks very much.
 
  • #6
Sorry we took so long!
 

FAQ: How can -x^3 + 27 be factored?

What is a cubic function?

A cubic function is a polynomial function of the form f(x) = ax^3 + bx^2 + cx + d, where a, b, c, and d are constants and x is the variable. It is called a cubic function because the highest power of x in the equation is 3.

What is factoring a cubic function?

Factoring a cubic function means breaking down the polynomial into its simplest form by finding its factors. This is done by finding the values of x that make the function equal to zero.

Why do we factor cubic functions?

Factoring a cubic function helps us solve equations and find the roots or x-intercepts of the function. It also helps us understand the behavior and shape of the graph of the function.

What are the methods for factoring a cubic function?

There are several methods for factoring a cubic function, including grouping, trial and error, and the cubic formula. The most commonly used method is the grouping method, where the polynomial is broken down into smaller polynomials that are easier to factor.

What are some tips for factoring cubic functions?

Some tips for factoring cubic functions include looking for common factors, grouping terms with similar variables, and using the sum and product method. It is also helpful to check if the given function is a perfect cube or can be rewritten in a simpler form before factoring.

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