MHB Radical Equation Solution: Simplifying and Transposing for Accurate Results?

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The equation $\sqrt{x} - \frac{2}{\sqrt{x}} = 1$ requires careful manipulation to find the correct solution. Transposing terms incorrectly can lead to errors, as seen when $1$ was dropped from the equation. The correct approach involves multiplying both sides by $\sqrt{x}$, resulting in $x - 2 = \sqrt{x}$. Squaring both sides will yield potential solutions, which must be verified against the original equation to avoid extraneous results. Ultimately, the solution process emphasizes the importance of maintaining all terms throughout the manipulation.
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$\sqrt{x}-\frac{2}{\sqrt{x}}=1$

transposing $\frac{2}{\sqrt{x}}$ to the right-side

$\sqrt{x}=\frac{2}{\sqrt{x}}$ multiply by $\sqrt{x}$

I get,

$x=2$ is my solution correct? if not please explain why. thanks!
 
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paulmdrdo said:
$\sqrt{x}-\frac{2}{\sqrt{x}}=1$

transposing $\frac{2}{\sqrt{x}}$ to the right-side

$\sqrt{x}=\frac{2}{\sqrt{x}}$ multiply by $\sqrt{x}$

I get,

$x=2$ is my solution correct? if not please explain why. thanks!

It is not right. becuase you dropped the 1

you will get
$\sqrt{x}=1+ \frac{2}{\sqrt{x}}$

but this approach shall not help

1st step is to multiply by $\sqrt{x}$ to remove redical from denominator
 
paulmdrdo said:
$\sqrt{x}-\frac{2}{\sqrt{x}}=1$

transposing $\frac{2}{\sqrt{x}}$ to the right-side

$\sqrt{x}=\frac{2}{\sqrt{x}}$ multiply by $\sqrt{x}$

I get,

$x=2$ is my solution correct? if not please explain why. thanks!
you can solve it in that way :
$$\sqrt{x}-\frac{2}{\sqrt{x}}=1$$
multiply by $$\sqrt{x}$$ and moving the other term to the other side :
$$x=1+2=3$$
hope that is right ..
=)
 
Maged Saeed said:
you can solve it in that way :
$$\sqrt{x}-\frac{2}{\sqrt{x}}=1$$
multiply by $$\sqrt{x}$$ and moving the other term to the other side :
$$x=1+2=3$$
hope that is right ..
=)

No, that isn't right, either.

If we multiply the equation:

$\sqrt{x} - \dfrac{2}{\sqrt{x}} = 1$

by $\sqrt{x}$, we obtain:

$x - 2 = \sqrt{x}$

Now, the best thing to do is square both sides. This will introduce an "extraneous" solution, so be sure to test both answers against the original problem.
 
I suggest letting $x=t^2$ if you don't prefer working with radicals , just like me.
 
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