Answer:
[tex]\boxed{x^3 + xy^2 + yx^2 + y^3}[/tex]
Step-by-step explanation:
[tex]\frac{x^4 - y^4}{x - y}[/tex]
[tex]= \frac{(x^2)^2 - (y^2)^2}{x - y}[/tex]
[tex]= \frac{(x^2 - y^2)(x^2 + y^2)}{x - y}[/tex]
[tex]= \frac{(x - y)(x + y)(x^2+y^2)}{x - y}[/tex]
[tex]= (x + y)(x^2 + y^2)[/tex]
[tex]= x^3 + xy^2 + yx^2 + y^3[/tex]
