\[1 - 2x + 2x^{3} - x^{5} = 0.\]
\[1)\ y^{'} = 0 - 2 + 2 \bullet 3x^{2} - 5x^{4} =\]
\[= - 5x^{4} + 6x^{2} - 2.\]
\[2)\ - 5x^{4} + 6x^{2} - 2 \geq 0\]
\[5x^{4} - 6x^{2} + 2 \leq 0\]
\[D = 36 - 40 = - 4 < 0\]
\[x \in \varnothing.\]
\[3)\ Функция\ убывает\ на\ R:\]
\[y(0) = 1 > 0.\]
\[Ответ:\ \ один.\]