Is There More Than One Solution for Cube Root Equations?

  • Thread starter Coco12
  • Start date
  • Tags
    Cube Root
In summary, the restrictions for a radical equation with a cubic function inside are to make the equation inside greater than or equal to 0. Unlike with a quadratic equation where there are positive and negative square roots, with a cubic equation there will be one real cube root and two complex conjugate roots. Additionally, when taking the nth root of a number, there will be n different roots.
  • #1
Coco12
272
0
Lets say I was trying to figure out the restrictions of a radical equation and the function inside the radical was a cubic function. I know you have to make the equation inside greater than or equal to 0.
In the case of a quadratic equation, you have to square root it once you bring everything to one side of the equality, giving you a positive and negative answer, is this the same for cube rooting it when figuring out the restrictions? You will have a positive and negative cube root?
 
Mathematics news on Phys.org
  • #3
Coco12 said:
Lets say I was trying to figure out the restrictions of a radical equation and the function inside the radical was a cubic function. I know you have to make the equation inside greater than or equal to 0.
In the case of a quadratic equation, you have to square root it once you bring everything to one side of the equality, giving you a positive and negative answer, is this the same for cube rooting it when figuring out the restrictions? You will have a positive and negative cube root?
No. [itex](-x)^3= -x^3[/itex] so there are not "positive and negative cube roots" of the same number. There will be one real cube root of a real number (other than 0) and two complex conjugate (non-real) roots.
 
  • #4
HallsofIvy said:
No. [itex](-x)^3= -x^3[/itex] so there are not "positive and negative cube roots" of the same number. There will be one real cube root of a real number (other than 0) and two complex conjugate (non-real) roots.

Ok thank you
 
  • #5

What is a cube root?

A cube root is a mathematical operation that determines the number that, when multiplied by itself three times, gives a given number. It is the opposite of cubing a number.

How do I calculate a cube root?

To calculate a cube root, you can use a calculator or a mathematical formula. The formula is: cube root of x = x^(1/3) where x is the number you want to find the cube root of.

What is the difference between a cube root and a square root?

A cube root is the number that, when multiplied by itself three times, gives a given number. A square root is the number that, when multiplied by itself, gives a given number. In other words, a cube root is the opposite of cubing a number, while a square root is the opposite of squaring a number.

Can a negative number have a cube root?

Yes, a negative number can have a cube root. However, it is important to note that a negative number multiplied by itself three times will always result in a negative number. Therefore, the cube root of a negative number will be a negative number, unless the negative sign is removed through mathematical manipulation.

What are some real-life applications of cube roots?

Cube roots are used in many scientific and engineering fields, such as physics, chemistry, and architecture. They are also commonly used in financial calculations, such as calculating compound interest. Additionally, cube roots are used in solving certain geometric problems, such as finding the side length of a cube with a known volume.

Similar threads

Replies
9
Views
10K
Replies
13
Views
3K
Replies
2
Views
750
  • General Math
Replies
16
Views
2K
Replies
14
Views
1K
  • General Math
Replies
16
Views
3K
Replies
4
Views
2K
  • Introductory Physics Homework Help
Replies
14
Views
596
  • General Math
Replies
2
Views
1K
Back
Top