a³ + b³ = (a + b)(a² - ab + b²)
a² - b² = (a - b)(a + b)
(х + 1)(х2 – x+1) - х(х+3)(х - 3) = x³ + 1³ - x(x² - 3²) = x³ + 1 - x³ + 9x = 9x + 1
при x = 1
9x +1 = 9*1 + 1 = 10
a³ + b³ = (a + b)(a² - ab + b²)
a² - b² = (a - b)(a + b)
(х + 1)(х2 – x+1) - х(х+3)(х - 3) = x³ + 1³ - x(x² - 3²) = x³ + 1 - x³ + 9x = 9x + 1
при x = 1
9x +1 = 9*1 + 1 = 10