1 a/xy+a/xu 2 m/ab-n/ac 3 5x^2-y^2/xy-3x-2y/y 4 5x/ab+2y/3a^2b-3/6a^b^2 5 2a-3b/a^2b-4a-5b/ab^2 6

Приведем выражения к общей дроби:

1) a/(x * y) + a/(x * u) = a/x * (1/y + 1/u) = a/x * (u + y)/(y * u) = a * (u + y)/(x * y * u); 

2) m/(a * b) - n/(a * c) = (m * c - n * b)/(a * b * c);

3) (5 * x^2 - y^2)/(x * y) - (3 * x - 2 * y)/y = (5 * x^2 - y^2 - x * (3 * x - 2 * y))/(x * y) = (5 * x^2 - y^2 - 3 * x^2 + 2 * x * y)/(x * y) = (2 * x^2 - y^2 + 2 * x * y)/(x * y); 

4) 5x/ab + 2y/3a^2b - 3/6a^2b^2 = 5x/ab + 2y/3a^2b - 1/2a^2b^2 = (5 * x * 6 * a * b + 2 * y * 2 * b - 1 * 3)/(6 * a^2 * b^2) = (30 * x * a * b + 4 * b^2 - 3)/(6 * a^2 * b^2); 

5) (2 * a - 3 * b)/(a^2 * b - 4 * a) - (5 * b)/(a * b^2) = (2 * a - 3 * b)/(a^2 * b - 4 * a) - 5/(a * b) = (a * b * (2 * a - 3 * b) - 5 * (2 * a - 3 * b))/(a^3 * b^2 - 4 * a^2 * b) = (2 * a^2 * b - 3 * a * b^2 - 10 * a + 15 * b)/(a^3 * b^2 - 4 * a^2 * b); 

6) (5 * a^2 - 2 * a - 1)/(a * b) - (3 * a - 2)/(a * b) = (5 * a^2 - 2 * a - 1 - 3 * a + 2)/(a * b) = (5 * a^2 - 5 * a + 1)/(a * b).