Представьте в виде рациональной дроби (5-b/a)/(2a/b-1)-((5a+b)/a-1)/((5a-b)/b+1).

\[\frac{5^{\backslash a} - \frac{b}{a}}{\frac{5a}{b} - 1^{\backslash b}} - \frac{\frac{5a + b}{b} - 1^{\backslash b}}{\frac{5a - b}{b} + 1^{\backslash b}} =\]

\[= \frac{\frac{5a - b}{a}}{\frac{5a - b}{b}} - \frac{\frac{5a + b - b}{b}}{\frac{5a - b + b}{b}} =\]

\[= \frac{5a - b}{a}\ :\frac{5a - b}{b} - \frac{5a}{b}\ :\frac{5a}{b} =\]

\[= \frac{b}{a} - 1^{\backslash a} = \frac{b - a}{a}\]