Vy\v set\v rete pr\accent23ub\v eh  funkc\' \i :
$$ f_1(x) = \sqrt{\frac{x^2}{(1 - x^2)^4}}, $$
$$f_2(x) = \root 3 \of{x^2 (x-6)}, $$
$$f_3(x) = \root 3 \of{x^2} - \root 3 \of{x^2-1}. $$
