Respuesta :

Answer:

Step-by-step explanation:

a) (a + b)² = (a + b) * (a +b)

  (a + b)³  = (a + b) * (a +b) * (a +b)

 a²- b² = (a +b) (a - b)

Here (a + b) is common in all the three expressions

HCF = (a + b)

b) (x - 1) = (x - 1)

  x² - 1  = (x - 1) * (x + 1)

  (x³ - 1) = (x - 1) (x² + x + 1)

HCF = (x -1)