Question

Bài 7 : Giải phương trình a, √2x + 1 = 2x + 1 b, √x + 1= 2x + 1

Answer 1

Giải giúp em với 

Answer 2

\(a,ĐK:x\ge-\dfrac{1}{2}\\ PT\Leftrightarrow\sqrt{2x+1}\left(\sqrt{2x+1}-1\right)=0\\ \Leftrightarrow\left\{{}\begin{matrix}2x+1=0\\2x+1=1\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}x=-\dfrac{1}{2}\left(tm\right)\\x=0\left(tm\right)\end{matrix}\right.\\ b,ĐK:x\ge-\dfrac{1}{2}\\ PT\Leftrightarrow x+1=4x^2+4x+1\\ \Leftrightarrow4x^2+3x=0\Leftrightarrow x\left(4x+3\right)=0\\ \Leftrightarrow\left[{}\begin{matrix}x=0\left(tm\right)\\x=-\dfrac{3}{4}\left(ktm\right)\end{matrix}\right.\Leftrightarrow x=0\)

Answer 3

b: \(\Leftrightarrow x\left(4x+3\right)=0\)

\(\Leftrightarrow\left[{}\begin{matrix}x=0\\x=-\dfrac{3}{4}\end{matrix}\right.\)