آیا تابع $f\left( x \right)=\left\{ \begin{matrix}   {{x}^{۲}}+۱\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,x\gt ۰  \\   {{x}^{۳}}-۱\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,x\lt ۰  \\   ۰\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,x=۰  \\\end{matrix} \right.$ در نقطه $x=۰$ پیوسته است؟