Question

Очень нужно! Срочно!!!

Answer 1

$\frac{6x^{-1}-y^{-1}}{6x^{-1}+y^{-1}}=\frac{\frac{6}{x}-\frac{1}{y}}{\frac{6}{x}+\frac{1}{y}}=\frac{\frac{6y-x}{xy}}{\frac{6y+x}{xy}} =\frac{6y-x}{6y+x}=\frac{\frac{6y}{x}-\frac{x}{x}}{\frac{6y}{x}+\frac{x}{x}}=\frac{6*\frac{y}{x}-1 }{6*\frac{y}{x}+1}=\frac{6*7^{-1}-1 }{6*7^{-1} +1}=\\\\=\frac{\frac{6}{7}-1 }{\frac{6}{7}+1 }=\frac{-\frac{1}{7} }{\frac{13}{7}}=\boxed{-\frac{1}{13}}$