Question

(x-2)(x²+2x+4)+(1+x)(x²-x+1)​

Answer 1

(a - b)(a² + ab + b²) = a³ - b³

(a + b)(a² - ab + b²) = a³ + b³

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(x - 2)(x² + 2x + 4) + (1 + x)(x² - x + 1) =

= (x - 2)(x² + 2x + 2²) + (x + 1)(x² - x + 1²) =

= x³ - 2³ + x³ + 1³ = 2x³ - 8 + 1 = 2x³ - 7