Question

\(\sqrt{2X-1}=3\)

\(\sqrt{7X}-\sqrt{2X-3}\)

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Answer 1

\(\sqrt{2x-1}\)=3

=2x-1=3

=2x=3+1

=2x=4

x=\(\dfrac{4}{2}\)

x=2

vậy x =2

sữa dê 1 chút nhé \(\sqrt{7x}\)-\(\sqrt{2x-3}\)=0

= 7x-2x-3=0

= 5x -3=0

= 5x =3

x= \(\dfrac{3}{5}\)

vậy x = \(\dfrac{3}{5}\)

\(\dfrac{3}{5}\)

Answer 2

\(\sqrt{2x-1}=3\Leftrightarrow2x-1=9\Leftrightarrow2x=10\Leftrightarrow x=5\)

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Answer 3

\(\sqrt{7x}-\sqrt{2x-3}=0\)

\(\Leftrightarrow\sqrt{7x}=\sqrt{2x-3}\)

\(\Leftrightarrow\left\{{}\begin{matrix}2x-3\ge0\\7x=2x-3\end{matrix}\right.\)

\(\Leftrightarrow\left\{{}\begin{matrix}x\ge\dfrac{3}{2}\\5x=-3\end{matrix}\right.\)

\(\Leftrightarrow\left\{{}\begin{matrix}x\ge\dfrac{3}{2}\\x=\dfrac{-3}{5}\end{matrix}\right.\)

(Vô lí )

Vậy pt vô nghiệm.