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Math Help - Radical fraction

  1. #1
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    Radical fraction

    how would I write 4/√7 with a fraction whose denominator is even?

    Thanks
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  2. #2
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    Re: Radical fraction

    Quote Originally Posted by drewm View Post
    how would I write 4/√7 with a fraction whose denominator is even?
    \frac{8\sqrt 7}{14}
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  3. #3
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    Re: Radical fraction

    ok thanks, but can you tell me how you got that?
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    Re: Radical fraction

    Quote Originally Posted by drewm View Post
    ok thanks, but can you tell me how you got that?
    I multiplied numerator and denominator by 2\sqrt 7~.
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  5. #5
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    Re: Radical fraction

    Quote Originally Posted by drewm View Post
    how would I write 4/√7 with a fraction whose denominator is even?

    Thanks
    If you think about it another way - you need to multiply top and bottom by \sqrt{7} to rationalise the denominator. However, 7 is not an even number so you must multiply top and bottom by 2 since multiplying any integer by 2 gives an even number.

    Plato did the same thing but combined the steps
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  6. #6
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    Re: Radical fraction

    \sqrt7\cdot\sqrt7=\sqrt{7\cdot7}=\sqrt{49}=7
    Like they said add 2 in front of the radical, there you would multiply 7\cdot2.
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