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    So I have this equation above. Looking at the exam question, I can see that you can divide each part by 4 to simplify it, giving 4-root5

    However, do you ever have to divide the 5 (inside the square root) by 4? I had a question the other day from a past paper, and for something like (4√5)/4, they had divided the 4 by four, but also divided the √5 by 4. It gave them an answer of like √(5/4).

    In the situation I described above, I don't mean the question used the same numbers as the first equation at the top of the page, but they used the same technique (with different numbers).

    Thanks
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    (Original post by blobbybill)
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    So I have this equation above. Looking at the exam question, I can see that you can divide each part by 4 to simplify it, giving 4-root5

    However, do you ever have to divide the 5 (inside the square root) by 4? I had a question the other day from a past paper, and for something like (4√5)/4, they had divided the 4 by four, but also divided the √5 by 4. It gave them an answer of like √(5/4).

    In the situation I described above, I don't mean the question used the same numbers as the first equation at the top of the page, but they used the same technique (with different numbers).

    Thanks
    You shouldn't be dividing the inside of the surd for questions like this. It can be useful to think of a surd as a letter in algebra so your example would be

    \displaystyle \frac{16-4x}{4}

    And that's equal to 4-x i.e. 4-\sqrt{5}

    Your other example also isn't a case where you divide the inside of the surd. It would be useful if you could remember the question since it's hard to guess what you mean.
 
 
 
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