Resposta :
[tex]\frac{1}{1+x^2}+\frac{10}{x^2+1}=\frac{x^2}{10} \\
\\
\frac{11}{x^2+1}=\frac{x^2}{10} \\
\\
x^4+x^2-110=0 \\
\\
\boxed{y=x^2} \\
\\
y^2+y-110=0 \\
\Delta=1^2-4.1.(-110)=1+440=441 \\
\\
y_1=\frac{-1-21}{2}=-11 \\
\\
y_2=\frac{-1+21}{2}= 10 \\
\\
x_1=+\sqrt{10} \\
\\
x_2=-\sqrt{10}
\\ \\ x_3=+\sqrt{11}i \\
\\
x_4=\sqrt{11}i[/tex]