Question

Помогите седьмой вопрос​

Answer 1

$\dfrac{x+1}{x-x^{2} } -\dfrac{x+3}{1-x^{2} } =\dfrac{x+1}{x(1-x) } -\dfrac{x+3}{(1-x)(1+x)} =\\\\\\=\dfrac{(x+1)(1+x)-(x+3)\cdot x}{x(1-x)(1+x)} =\dfrac{x+x^{2} +1+x-x^{2} -3x}{x(1-x)(1+x)} \\\\\\=\dfrac{1-x}{x(1-x)(1+x)} =\boxed{\dfrac{1}{x+x^{2} } }$