Докажите тождество.
(x^ 2 +6x+9)(x^ 3 -9x^ 2 +27x-27)(x+3)=(x^ 2 -9)^ 3

a² - b² = (a - b)(a + b)
(a + b)² = a² + 2ab + b²
(a - b)³ = a³ - 3a²b + 3ab² - b³
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x³ -9x² +27x-27 = x³ - 3*x²*3 + 3*3²*x - 3³ = (x - 3)³
(x² +6x+9)(x³ -9x² +27x-27)(x+3)=(x + 3)²(x - 3)³(x + 3) = ((x + 3)(x - 3))³ = (x² -9)³ чтд