Question

3x- căn (x+1)+1=0 giải Pt và xác định Đk

Answer 1

\(ĐK:x\ge\dfrac{1}{3}\\ PT\Leftrightarrow\sqrt{x+1}=3x-1\\ \Leftrightarrow x+1=9x^2-6x+1\\ \Leftrightarrow9x^2-7x=0\\ \Leftrightarrow\left[{}\begin{matrix}x=0\left(ktm\right)\\x=\dfrac{7}{9}\left(tm\right)\end{matrix}\right.\Leftrightarrow x=\dfrac{7}{9}\)

Answer 2

\(\Leftrightarrow\sqrt{x+1}=3x-1\)

\(\Leftrightarrow\left[{}\begin{matrix}x=0\\x=\dfrac{7}{9}\end{matrix}\right.\)