Вправи: 1359

1359. Розклади на множники.

а) а² – b² + х² – y² + 2ax + 2by = a² + 2ax + x² – (b² – 2by + y²) = (a + x)² – (b – y)² = (a + x – b + y)(a + x + b – y);

б) x⁴ + y⁴ – x² – y² + 2x²y² – 2xy = x⁴ + 2x²y² + y⁴ – (x² + 2xy + y²) = (x² + y²)² – (x + y)² = (x² + y² – x – y)(x² + y² + x + y).