Розділ 2. РОЗКЛАДАННЯ МНОГОЧЛЕНІВ » 595

Розв’яжи рівняння. а) (x³ + 3)(х6 – 3x³ + 9) – 26 = 0; (x³)3 + 3³ = 26; x9 + 27 = 26; x9 = 26 – 27; x9 = –1; x = –1. б) (x – 2)(x² + 2x + 4) – (x + 4)(x² – 4x + 16) = 6(2x – 9); x³ – 2³ – (x³ + 4³) = 12x – 54; x³ – 8 – x³ – 64 = 12x – 54; 12x – 54 = –72; 12x = –18| : 12; x = –1,5. в) (x + 5)(x² – 5x + 25) – x(х – 4)(x + 4) = –3; x3 + 5³ – x(x² – 16) = –3; x³ + 125 – x³ + 16x = –3; 16х = –3 – 125; 16х = –128| : 16; x = –8. г) (x² – 4)(x² – 2x + 4) = x³(x – 2); (x – 2)(x + 2)(x² – 2x + 4) = x³(x – 2); (x – 2)(x³ + 2³) = x³(x – 2); (x – 2)(x³ + 8) – x³(x – 2) = 0; (x – 2)(x³ + 8 – x³) = 0; (x – 2) • 8 = 0; 8х – 16 = 0; 8х = 16 | : 8; x = 2.