Proving $(a)^\dfrac{1}{3}+(b)^\dfrac{1}{3}+(c)^\dfrac{1}{3}=0$

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In summary, using the given equations, we can prove that the sum of the cube roots of $a, b,$ and $c$ is equal to zero. This is done by using the identity $(x^3+y^3+z^3-3xyz)=\dfrac{1}{2}(x+y+z)((x-y)^2+(y-z)^2+(z-x)^2)$ and the fact that $x+y+z=0$. Therefore, the statement $(a)^\dfrac{1}{3}+(b)^\dfrac{1}{3}+(c)^\dfrac{1}{3}=0$ is proven.
  • #1
solakis1
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Given:
$a+b+c-3(abc)^\dfrac{1}{3}=0$ and $\neg((a)^\dfrac{1}{3}=(b)^\dfrac{1}{3}) $ and $\neg((b)^\dfrac{1}{3}=(c)^\dfrac{1}{3})$ and
$\neg((c)^\dfrac{1}{3}=(a)^\dfrac{1}{3})$
Then prove:

$(a)^\dfrac{1}{3}+(b)^\dfrac{1}{3}+(c)^\dfrac{1}{3}=0$
 
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  • #2
solakis said:
Given:
$a+b+c-3(abc)^\dfrac{1}{3}=0$............(1)

$\neg((a)^\dfrac{1}{3}=(b)^\dfrac{1}{3}) $ .......(2)
$\neg((b)^\dfrac{1}{3}=(c)^\dfrac{1}{3})$ .......(3)
$\neg((c)^\dfrac{1}{3}=(a)^\dfrac{1}{3})$.........(4)
Then prove:

$(a)^\dfrac{1}{3}+(b)^\dfrac{1}{3}+(c)^\dfrac{1}{3}=0$
[sp] Let : $x=a^\dfrac{1}{3},y=b^\dfrac{1}{3},z=c^\dfrac{1}{3}$.........(5)
Use the following identity:

$(x^3+y^3+z^3-3xyz)=\dfrac{1}{2}(x+y+z)((x-y)^2+(y-z)^2+(z-x)^2)$.......(6)

Use (1),(2),(3) ,(4),(5) and (6) becomes:

$ (a)^\dfrac{1}{3}+(b)^\dfrac{1}{3}+(c)^\dfrac{1}{3}=0$
Since:
$x+y+z=0$[/sp]
 

1. How can I prove that $(a)^\dfrac{1}{3}+(b)^\dfrac{1}{3}+(c)^\dfrac{1}{3}=0$?

There are a few different ways to approach this proof. One method is to use the concept of a cube root and its properties, such as the fact that the cube root of a product is equal to the product of the cube roots. Another approach is to use algebraic manipulation and substitution to simplify the expression and show that it equals zero.

2. Is there a specific set of values for $a$, $b$, and $c$ that will make the equation true?

Yes, there are certain values for $a$, $b$, and $c$ that will make the equation $(a)^\dfrac{1}{3}+(b)^\dfrac{1}{3}+(c)^\dfrac{1}{3}=0$ true. For example, if $a$, $b$, and $c$ are all equal to zero, the equation will be true. Additionally, any set of values where the sum of the cube roots is equal to zero, such as $a=8$, $b=-8$, and $c=0$, will satisfy the equation.

3. Can this equation be used to solve for a specific variable?

No, this equation cannot be used to solve for a specific variable. It is an expression that must be true for certain values of $a$, $b$, and $c$, but it does not provide a way to solve for any one variable. In order to solve for a specific variable, additional information or equations would be needed.

4. What are some real-world applications of this equation?

This equation may be used in various fields of science and engineering, such as physics and chemistry. For example, it could be used in calculations involving the properties of gases or the behavior of certain chemical reactions. It may also have applications in computer science and cryptography.

5. Is this equation always true, or are there exceptions?

The equation $(a)^\dfrac{1}{3}+(b)^\dfrac{1}{3}+(c)^\dfrac{1}{3}=0$ is not always true. As mentioned in the answer to the second question, there are specific values for $a$, $b$, and $c$ that will make the equation true, but there are also many values where it will not be true. For example, if $a$, $b$, and $c$ are all negative, the equation will not be true. Additionally, if only one of the variables is negative, the equation will not be true. It is important to consider the values of $a$, $b$, and $c$ when determining if the equation is true or not.

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