20 Вправа 20Алгебра 8 клас Бевз 2025 · § 1 · стор. 10

а) ${\displaystyle \frac{2}{x(1+x)}}$

${\displaystyle x\ne 0}$, ${\displaystyle 1+x\ne 0}$;

${\displaystyle x\ne 0}$, ${\displaystyle x\ne -1}$;

б) ${\displaystyle \frac{1+x^2}{1-x^2}}$

${\displaystyle 1-x^2\ne 0}$;

${\displaystyle x^2\ne 1}$;

${\displaystyle x\ne \pm 1}$;

в) ${\displaystyle \frac{3}{4x-x^3}}$

${\displaystyle x(4-x^2)\ne 0}$;

${\displaystyle x\ne 0}$, ${\displaystyle x^2\ne 4}$;

${\displaystyle x\ne 0}$, ${\displaystyle x\ne \pm 2}$;

г) ${\displaystyle \frac{1-x^2}{1+x^2}}$

${\displaystyle 1+x^2>0}$;

x — будь-яке.