Question

Упростите выражение 1/х-1 - 1/х+1

Answer 1

$frac{1}{x-1} - frac{1}{x+1} = frac{x+1}{(x-1)(x+1)} - frac{x-1}{(x-1)(x+1)} = frac{x+1-x+1}{(x-1)(x+1)} = frac{2}{ x^{2} -1}$