Nguyễn Hưng Phát
16/11/2017 at 13:33-
We have :
\(\left[{}\begin{matrix}x-2017=0\\x^2-2018^2=0\\x^3-2019^3=0\\x^4-2020^4=0\end{matrix}\right.\Rightarrow\left[{}\begin{matrix}x=2017\\x=\pm2018\\x=2019\\x=\pm2020\end{matrix}\right.\)
So, the equation has 6 roots above
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