ĐKXĐ: \(x\in R\)
\(pt\Leftrightarrow\sqrt{\left(x+2\right)^2}=5-x^2\)
\(\Leftrightarrow\left|x+2\right|=5-x^2\left(1\right)\)
TH1: \(x\ge-2\)
\(\left(1\right)\Leftrightarrow x+2=5-x^2\)
\(\Leftrightarrow x^2+x-3=0\)
\(\Leftrightarrow\left[{}\begin{matrix}x=\frac{-1+\sqrt{13}}{2}\left(tm\right)\\x=\frac{-1-\sqrt{13}}{2}\left(l\right)\end{matrix}\right.\)
TH2: \(x< 2\)
\(\left(1\right)\Leftrightarrow-x-2=5-x^2\)
\(\Leftrightarrow x^2-x-7=0\)
\(\Leftrightarrow\left[{}\begin{matrix}x=\frac{1+\sqrt{29}}{2}\left(l\right)\\x=\frac{1-\sqrt{29}}{2}\left(tm\right)\end{matrix}\right.\)
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