Розділ 4. ЛІНІЙНІ РІВНЯННЯ ТА СИСТЕМИ » 881

Solve only those equations that can be reduced to linear equations. b) (x + 3)2 – (x – 3)2 = 12; (x + 3 – (x – 3))(x + 3 + x – 3) = 12; (x + 3 – x + 3) • 2x = 12; 6 • 2x = 12; 12x = 12; x = 1. c) (2x – 1)(4x2 + 2x + 1) = x(3x – 2)(3x + 2) – x3; 4x3 + 4x2 + 2x – 4x2 – 2x – 1 = x(9x2 – 4) – x3; 8x3 – 1 = 9x3 – 4x – x3; 8x3 – 9x3 + x3 + 4x = 1; 4x = 1| :4; x = 0,25. e) (3,7x – 2)(3,7x + 2) – (1,3x – 1)(1,3x + 1) = 6x(2x – 1); 13,69x2 – 4 – (1,69x2 – 1) = 12x2 – 6x; 13,69x2 – 4 – 1,69x2 + 1 – 12x2 + 6x = 0; 6x = 3|: 6; x = 3/6; x = 0,5.