Question

Giải phương trình:

a)\(\sqrt{2}x-\sqrt{50}=0\)

b)\(\sqrt[3]{x+1}=2\)

c)\(\sqrt{\left(x-3\right)^2}=3-x\)

d)\(\sqrt{2x+5}=\sqrt{1-x}\)

e)\(|x^2-1|+|x+1|=0\)

f)​\(|3x^{ }+1|=|x+1|\)​​v

\(|x^2-1|+|x+1|=0\)​

Answer 1

c) ĐKXĐ: \(x\in R\)

PT\(\Leftrightarrow\left|x-3\right|=3-x=-\left(x-3\right)\)

\(\Rightarrow x-3< 0\)\(\Leftrightarrow x< 3\)

d) ĐKXĐ: \(\frac{-5}{2}\le x\le1\)

PT\(\Leftrightarrow2x+5=1-x\Leftrightarrow3x=-4\Leftrightarrow x=\frac{-4}{3}\)

Answer 2

e) \(\left|x^2-1\right|+\left|x+1\right|=0\)

\(\Rightarrow\left\{{}\begin{matrix}x^2-1=0\\x+1=0\end{matrix}\right.\Leftrightarrow}\left\{{}\begin{matrix}x^2=1\\x=-1\end{matrix}\right.\Leftrightarrow x=-1}\)

Answer 3

a <=> \(\sqrt{2}\) x - \(\sqrt{2}\) . \(\sqrt{25}\) = 0

<=> \(\sqrt{2}\) . ( x-\(\sqrt{25}\) )=0

<=> x-\(\sqrt{25}\) =0

<=> x=\(\sqrt{25}\)

Answer 4

b) \(\sqrt[3]{x+1}=2\Rightarrow x+1=8\Leftrightarrow x=7\)