Find each of the following products:

(x² – xy + y²) × (x + y)

By using horizontal method,

We have;

= (x² – xy + y²) × (x + y)

= x(x² – xy + y²) + y(x² – xy + y²)

= x³ - x²y + xy² + x²y – xy² + y³

By arranging the expression in the form of descending powers of x,

We get;

= (x³ + y³)