Question

Выполните действия:

а)3/а+(а-3)/(а+5)

б)(2х^2)/(х^2-4)-2х/х+2

Answer 1

$...........=\frac{3(a+5)+a(a-3)}{a(a+5)} = \frac{3a+15+ a^{2} -3a}{a(a+5)} = \frac{ a^{2} +15}{a(a+5)} \\ \\ \\ \\ .............= \frac{2 x^{2} }{(x-2)(x+2)}- \frac{2x}{x+2} = \frac{2 x^{2} -2(x-2)}{(x+2)(x-2)} = \frac{2 x^{2} -2x+4}{(x+2)(x-2)} = \frac{2( x^{2} -x+2)}{ x^{2} -4}$