Đặt x + t = 2 thì:
\(\left(t-1\right)^4+\left(t+1\right)^4=82\Rightarrow2t^4+12t^2+2=82\Rightarrow t^4+6t^2+1=41\Rightarrow t^4+6t^2+9=49\Rightarrow\left(t^2+3\right)^2=49\Rightarrow t^2=4\Rightarrow t\in\left\{2;-2\right\}\Rightarrow x\in\left\{0;-4\right\}\)
