Question

Tìm x biết :
\(\sqrt{x^2}\)= I-4 I

Answer 1

\(\sqrt{x^2}=\left|-4\right|\)

\(\Rightarrow\left|x\right|=4\)

\(\Rightarrow\orbr{\begin{cases}x=4\\x=-4\end{cases}}\)

Answer 2

\(\sqrt{x^2}=\left|-4\right|\)

\(\Rightarrow\left|x\right|=\left|-4\right|\)

\(\Rightarrow\orbr{\begin{cases}x=4\\x=-4\end{cases}}\)

Answer 3

\(\sqrt{x^2}=\left|-4\right|\)

\(\sqrt{x^2}=4\)

\(\Rightarrow\hept{\begin{cases}x=4\\x=-4\end{cases}}\)

Answer 4

\(\sqrt{x^2}=\left|-4\right|\)

=>\(\left|x\right|=4\)

=>\(\orbr{\begin{cases}x=-4\\x=4\end{cases}}\)