Question

Tìm x :

a) (\(\sqrt{x}\)-1)^2= 0,5625

b) 2\(\sqrt{x}\)-x=0

c) x+\(\sqrt{x}\)=0

Answer 1

a: \(\left(\sqrt{x}-1\right)^2=0.5625=\dfrac{9}{16}\)

\(\Leftrightarrow\left[{}\begin{matrix}\sqrt{x}-1=\dfrac{3}{4}\\\sqrt{x}-1=-\dfrac{3}{4}\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}\sqrt{x}=\dfrac{7}{4}\\\sqrt{x}=\dfrac{1}{4}\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{49}{16}\\x=\dfrac{1}{16}\end{matrix}\right.\)

b: \(2\sqrt{x}-x=0\)

\(\Leftrightarrow\sqrt{x}\left(2-\sqrt{x}\right)=0\)

=>x=0 hoặc x=4

c: \(x+\sqrt{x}=0\)

\(\Leftrightarrow\sqrt{x}\left(\sqrt{x}+1\right)=0\)

=>x=0