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2nd to last step of Completing the Square, how does adding 2 give this? watch

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    I get that x-2=.... goes to x=2.... when you add 2 to both sides, that's obvious. However, I don't get why adding the two changes the +/- square root of 1/2 into 1/square root of 2.

    Why does adding the two change the position of the root 2 in the equation? It goes from bring the root of 1/2, to 1/root 2

    Thanks

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     \sqrt{\frac{1}{2}} = \frac{\sqrt{1}}{\sqrt{2}} = \frac{1}{\sqrt{2}}
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    (Original post by NotNotBatman)
     \sqrt{\frac{1}{2}} = \frac{\sqrt{1}}{\sqrt{2}} = \frac{1}{\sqrt{2}}
    Oh, they have just written it as the simplest form?
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    (Original post by blobbybill)
    Oh, they have just written it as the simplest form?
    Not the simplest, but rewritten in another form with the same value.
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    (Original post by blobbybill)
    Oh, they have just written it as the simplest form?
    Yes, through the book they give answers in their simplest forms, so its a good habit to get used to simplifying your answers too
 
 
 
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