Вправи: 243

243. Знайдіть корені рівняння:

1) 2x+1x – 3 = 0; 2x+1-3x = 0; 1-xx = 0; 1 – x = 0, x = 1,

x ≠ 0; x ≠ 0; x = 1.

2) xx-4 = 5; x = 5(x – 4), x = 5x – 20, 4x = 20, x = 5,

х ≠ 4; x ≠ 4; x ≠ 4; x ≠ 4; x = 5.

3) xx+2 = 53; 3х = 5(x + 2), 3х = 5x + 10, 2x = –10, x = –5,

x ≠ –2; x ≠ –2; x ≠ –2; x ≠ –2;

x = –5.

4) 5x-2 = 3x+4; 5(x + 4) = 3(x – 2), 5x + 20 = 3х – 6, 2x = –26,

x ≠ 2, x ≠ 2, x ≠ 2,

x ≠ –4; x = –4; x = –4;

x = –13.