# Homework Help: Express x⁴ + y⁴ + z⁴ - 2y²z² - 2z²x² - 2x²y² as the product of four factors.

1. Nov 24, 2009

### MorallyObtuse

1. The problem statement, all variables and given/known data

Express $$x^4 + y^4 + z^4 - 2y^2z^2 - 2z^2x^2 - 2x^2y^2$$ as the product of four factors.

2. The attempt at a solution

$$(x-y-z)(-x+y-z)(-x-y+z)(x+y+z)$$

2. Nov 24, 2009

### Dick

If you really just want someone to check, that works fine.

3. Nov 24, 2009

Ok, thanks!