Vì : \(\left(x-1\right)\left(x^3+1\right)\left(x^2-49\right)=0\)
\(\Rightarrow\hept{\begin{cases}x-1=0\\x^3+1=0\\x^2-49=0\end{cases}\Leftrightarrow\hept{\begin{cases}x=0+1=1\\x^3=-1\Rightarrow x=-1\\x^2=49\Rightarrow x=7\end{cases}}}\)
Vậy ...
x-1=0=> x=1
hoặc
x^3+1=0=> x=-1
hoặc
x^2-49=0=> x=7 hoặc -7
kết luận
x=+-7, +-1
\(\left(x-1\right)\left(x^3+1\right)\left(x^2-49\right)=0\)
\(\Rightarrow\hept{\begin{cases}x-1=0\\x^3+1=0\\x^2-49=0\end{cases}}\) \(\Rightarrow\hept{\begin{cases}x=0+1\\x^3=0+1\\x^2=0+49\end{cases}}\) \(\Rightarrow\hept{\begin{cases}x=1\\x^3=1\\x^2=49\end{cases}}\)
\(\Rightarrow\hept{\begin{cases}x=1\\x=1\\x=\pm7\end{cases}}\)
\(\Rightarrow x\in\left\{1\text{ },\text{ }\pm7\right\}\)
