Question

Cho A = \(\sqrt{2x+10}\)

Tìm x để A = \(x+1\)

Answer 1

\(\Leftrightarrow x^2+2x+1=2x+10\)

=>x^2+1=10

=>x=3(nhận) hoặc x=-3(loại)

Answer 2

\(\Leftrightarrow x+1=\sqrt{2x+10}\)

\(\Leftrightarrow x^2+2x+1=2x+10\)

\(\)\(\)\(\Leftrightarrow x^2-9=0\)

\(\Leftrightarrow\left(x-3\right)\left(x+3\right)=0\)

\(\Rightarrow\left[{}\begin{matrix}x=3\\x=-3\end{matrix}\right.\)