Is There More Than One Solution for Cube Root Equations?

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Discussion Overview

The discussion revolves around the nature of solutions for cube root equations, particularly in relation to the restrictions of radical equations involving cubic functions. Participants explore the similarities and differences between cube roots and square roots, as well as the number of roots associated with cubic equations.

Discussion Character

  • Exploratory
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • One participant questions whether cube rooting a cubic function yields both positive and negative roots, similar to square roots in quadratic equations.
  • Another participant asserts that a cubic equation should have three roots when factored, referencing an external article for additional context.
  • A later reply clarifies that there are not "positive and negative cube roots" of the same number, stating that there is one real cube root and two complex conjugate roots for a real number (other than 0).
  • Another participant reiterates the point about the uniqueness of the real cube root and the existence of complex roots, confirming the earlier clarification.
  • One participant mentions that taking the nth root of a number results in n different roots, suggesting a broader perspective on root solutions.

Areas of Agreement / Disagreement

Participants express differing views on the nature of cube roots compared to square roots, with some asserting the uniqueness of real cube roots while others suggest a misunderstanding of the concept. The discussion remains unresolved regarding the implications of these differences.

Contextual Notes

The discussion includes assumptions about the nature of roots and the definitions of cube and square roots, which may not be universally agreed upon. There are also references to external articles that may provide additional context but do not resolve the ongoing debate.

Who May Find This Useful

Readers interested in the mathematical properties of radical equations, particularly those studying cubic functions and their roots, may find this discussion relevant.

Coco12
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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?
 
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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. (-x)^3= -x^3 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.
 
HallsofIvy said:
No. (-x)^3= -x^3 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
 

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