Выполни действия с алгебраическими дробями: $\frac{16}{x^2} - \frac{x-4}{x-4}$

a) $\frac{16}{x^2} - \frac{x-4}{x-4} = \frac{16}{x^2} - 1 = \frac{16 - x^2}{x^2} = \frac{(4 - x)(4 + x)}{x^2}$ б) $\frac{25}{a^2} - \frac{a+5}{a+5} = \frac{25}{a^2} - 1 = \frac{25 - a^2}{a^2} = \frac{(5 - a)(5 + a)}{a^2}$ в) $\frac{3a-1}{a^2-b^2} - \frac{3b-1}{a^2-b^2} = \frac{3a - 1 - (3b - 1)}{a^2 - b^2} = \frac{3a - 3b}{a^2 - b^2} = \frac{3(a - b)}{(a - b)(a + b)} = \frac{3}{a + b}$ г) $\frac{x-3}{x^2-64} + \frac{11}{x^2-64} = \frac{x - 3 + 11}{x^2 - 64} = \frac{x + 8}{x^2 - 64} = \frac{x + 8}{(x - 8)(x + 8)} = \frac{1}{x - 8}$ д) $\frac{2a+b}{(a-b)^2} - \frac{2b-5a}{(a-b)^2} = \frac{2a + b - (2b - 5a)}{(a-b)^2} = \frac{2a + b - 2b + 5a}{(a-b)^2} = \frac{7a - b}{(a-b)^2}$ е) $\frac{13x+6y}{(x+y)^2} - \frac{11x+4y}{(x+y)^2} = \frac{13x + 6y - (11x + 4y)}{(x+y)^2} = \frac{13x + 6y - 11x - 4y}{(x+y)^2} = \frac{2x + 2y}{(x+y)^2} = \frac{2(x + y)}{(x+y)^2} = \frac{2}{x+y}$