1.
а) x^2 - 9 / x - 3 = (x - 3)(x + 3) / x - 3 = x + 3;
б) x^2 + 2x + 1 / x + 1 = (x + 1)^2 / x + 1 = x + 1;
2.
x^2 - x / 2y • y / x - 1 = y(x^2 - x) / 2y(x - 1) = xy( x - 1) / 2y(x - 1) = x/y.
3.
a) 2x + 1 = 3 - x
2x + x = 3 - 1
3x = 2
x = 2/3
Ответ: 2/3.
б) 2x - 1 / 3 + x + 1 / 2 = 2
4x - 2 + 3x + 3 / 6 = 2
7x + 1 / 6 = 2
7x + 1 = 2 • 6
7x + 1 = 12
7x = 12 - 1
7x = 11
x = 1 4/7
Ответ: 1 4/7.