(x2-y2)3+(y2-z2)3+(z 2-x 2)3/(x-y)3+(y-z)3+(z-x)3

3 min read Jun 17, 2024
(x2-y2)3+(y2-z2)3+(z 2-x 2)3/(x-y)3+(y-z)3+(z-x)3

Simplifying the Expression: (x²-y²)³ + (y²-z²)³ + (z²-x²)³ / (x-y)³ + (y-z)³ + (z-x)³

This expression appears complex, but we can simplify it using algebraic manipulation and a key factorization formula. Let's break it down step by step:

Understanding the Key Factorization

The core of simplifying this expression lies in recognizing the following factorization:

a³ + b³ + c³ - 3abc = (a + b + c)(a² + b² + c² - ab - ac - bc)

This formula holds true for any values of 'a', 'b', and 'c'.

Applying the Factorization

Let's apply this formula to our expression:

  1. Identify the terms: We have (x²-y²), (y²-z²), and (z²-x²) as our 'a', 'b', and 'c' respectively.

  2. Calculate the necessary components:

    • (x²-y²) + (y²-z²) + (z²-x²) = 0
    • (x²-y²)² + (y²-z²)² + (z²-x²)² = 2(x⁴ + y⁴ + z⁴ - x²y² - x²z² - y²z²)
    • (x²-y²)(y²-z²)(z²-x²) = (x²-y²)(z²-x²)(y²-z²) (Note the rearrangement)
  3. Substitute into the factorization formula: (x²-y²)³ + (y²-z²)³ + (z²-x²)³ - 3(x²-y²)(y²-z²)(z²-x²) = (0) * [2(x⁴ + y⁴ + z⁴ - x²y² - x²z² - y²z²) - (x²-y²)(z²-x²)(y²-z²)]

Simplifying the Denominator

Now let's look at the denominator:

  1. Apply the difference of cubes formula:

    • (x-y)³ = x³ - 3x²y + 3xy² - y³
    • (y-z)³ = y³ - 3y²z + 3yz² - z³
    • (z-x)³ = z³ - 3z²x + 3zx² - x³
  2. Add the terms together: (x-y)³ + (y-z)³ + (z-x)³ = -3(x²y - xy² + y²z - yz² + z²x - zx²)

Combining the Simplified Expressions

Our simplified expression now looks like this:

0 / -3(x²y - xy² + y²z - yz² + z²x - zx²)

Final Result

Any number divided by 0 is undefined. Therefore, the simplified form of the given expression is undefined.

It's important to note that this expression is undefined for any values of x, y, and z where the denominator (x²y - xy² + y²z - yz² + z²x - zx²) equals 0.

Featured Posts