square roots are fantastic...

[eyb0ss]

English isn't my mother tongue, so I might make mistakes.

I have to simplify sqrt(x + 2*sqrt(x - 4)) where x>=4 (is greater or equal to 4) and I don't know how I should start. When i first saw it I thought it was simplified already, but apparently not...

 

[pka]

I have to simplify sqrt(x + 2*sqrt(x - 4)) where x>=4 (is greater or equal to 4)

\(\displaystyle \sqrt{x+2\cdot\sqrt{x-4}}\) is a simplified term already.

Is this part of a larger question? You need to post the entire question in its exact wording.

 

[eyb0ss]

No, this is how the problem starts, no changes to it whatsoever.

 

[Ishuda]

English isn't my mother tongue, so I might make mistakes.

I have to simplify sqrt(x + 2*sqrt(x - 4)) where x>=4 (is greater or equal to 4) and I don't know how I should start. When i first saw it I thought it was simplified already, but apparently not...

As pka said, it is simplified. You can move some things around, but I really wouldn't really call it simplification, i.e.
\(\displaystyle \sqrt{x+2\sqrt{x-4}}\, =\, \sqrt{\sqrt{x-4}\, [2 + \sqrt{x-4}]\, +\, 4}\)

EDIT: Fixed dumb mistake [thanks Subhotosh Khan]

 

[Otis]

... this is how the problem starts, no changes to it whatsoever.

:idea: This exercise may contain a typographical error.