Х во 2 - 25 1 х+5 ------------- * ------------ - --------------- х+6 х во 2 +5х х во 2 -...

$\frac{x^2-25}{x+6} * \frac{1}{x^2+5x} - \frac{x+5}{x^2-6x} = \\ \\ = \frac{(x-5)(x+5) * 1 }{(x+6) * x(x+5) } - \frac{x+5}{x(x-6)} = \\ \\ = \frac{x-5}{x(x+6)} - \frac{x+5}{x(x-6)} = \\ \\ = \frac{(x-5)(x-6) - (x+5)(x+6)}{x(x+6)(x-6)} = \\ \\ = \frac{x^2-6x-5x+30 - x^2-6x-5x-30}{x(x^2-6^2)} = \\ \\ = \frac{-22x}{x(x^2-36)} = - \frac{22}{x^2-36}$
Ответ : 4)

$\frac{x+3}{x^2 + 9 } * ( \frac{x+3}{x-3} + \frac{x-3}{x+3} )= \\ \\ = \frac{x+3}{x^2 + 9} * \frac{(x+3)(x+3) + (x-3)(x-3)}{(x-3)(x+3)} = \\ \\ = \frac{x+3}{x^2 + 3^2} * \frac{(x+3)^2 +(x-3)^2}{x^2 - 3^2} = \\ \\ = \frac{x+3}{x^2 + 3^2} * \frac{x^2 +6x+3^2 + x^2 -6x+3^2}{(x^2-3^2)} = \\ \\ = \frac{(x+3)(2x^2+18)}{(x^2+9)(x^2-9)} = \frac{2(x+3)(x^2+9)}{(x^2+9)(x+3)(x-3)} = \\ \\ = \frac{2}{x-3} \\ \\ x=1.75 \\ \frac{2}{1.75 - 3} = \frac{2}{-1.25} = -1.6$
Ответ: 2)