Разложите на множители. 1) b2-c2-b+c; 2) a+b-a2+b2; 3) a3+a2-a-1; 4) b2-bc-a2+ac.

1) b² - c² - b + c = (b² - c²) - (b - c) = (b - c) * (b + c) - (b - c) = (b - c) * (b + c - 1)

2) a + b - a² + b² = (a + b) - a² + b² = (a + b) - (a - b) * (a + b) = (a + b) * (1 - a + b)

3) a³ + a² - a - 1 = (a³ + a² ) - (a + 1) = a² (a + 1 ) - (a + 1) = (a² - 1 ) * (a + 1)

4) b² - bc - a² + ac = (b² - a² ) - (bc - ac) = (b - a) * (b - a) - c * (b - a) = (b - a) * (b + a - c)