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    Express 2/ 3-√3 in the form a+b√3, where a and b are rational numbers to be found
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    (Original post by Mathsgu)
    Express 2/ 3-√3 in the form a+b√3, where a and b are rational numbers to be found
    rationalise the denominator by multiplying both the top and bottom by 3+√3
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    (Original post by Mathsgu)
    Express 2/ 3-√3 in the form a+b√3, where a and b are rational numbers to be found
    Try rationalising the denominator, i.e. times the numerator and the denominator by 3+√3

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    (Original post by Ben4)
    Try rationalising the denominator, i.e. times the numerator and the denominator by 3+√3

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    Thank you, what would be the next steps in working this out? I rationalized this last time but did not get the right answer
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    (Original post by Mathsgu)
    Thank you, what would be the next steps in working this out? I rationalized this last time but did not get the right answer
    Can I see your workings? Maybe you didnt simplify it correctly.

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    (Original post by Mathsgu)
    Thank you, what would be the next steps in working this out? I rationalized this last time but did not get the right answer
    We can't post the answer but will look at your working to help you.
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    times that numerator by 3+√3 but the denominator by 3-√3
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    (Original post by Suprite)
    times that numerator by 3+√3 but the denominator by 3-√3
    no - you must multiply numerator and denominator by the same or you won't have an equivalent fraction!
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    (Original post by Suprite)
    times that numerator by 3+√3 but the denominator by 3-√3
    This is just wrong \frac{3+\sqrt{3}}{3 - \sqrt{3}} \neq 1.
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    [QUOTE=Ben4;60086169]Can I see your workings? Maybe you didnt simplify it correctly.

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    Yeah sure I worked it out like this. I tried rationalizing it to begin with by times the top and bottom by 3+squareroot 3 and I ended up with 6+ 2squareroot 3 over 6. I'm most likely multiplying it in the wrong way but I don't know where i'm going wrong.
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    (Original post by Mathsgu)
    Yeah sure I worked it out like this. I tried rationalizing it to begin with by times the top and bottom by 3+squareroot 3 and I ended up with 6+ 2squareroot 3 over 6. I'm most likely multiplying it in the wrong way but I don't know where i'm going wrong.
    This is correct. Simplify it down and you get 1+(1/3)rt3
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    [QUOTE=Mathsgu;60126653]
    (Original post by Ben4)
    Can I see your workings? Maybe you didnt simplify it correctly.

    Posted from TSR Mobile[/QUOTE
    Yeah sure I worked it out like this. I tried rationalizing it to begin with by times the top and bottom by 3+squareroot 3 and I ended up with 6+ 2squareroot 3 over 6. I'm most likely multiplying it in the wrong way but I don't know where i'm going wrong.
    \displaystyle \frac{6 + 2\sqrt{3}}{6} = \frac{6}{6} + \frac{2}{6}\sqrt{3}
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    (Original post by C0pper)
    Assuming you mean rt3 there instead of rt5, this is correct. Simplify it down and you get 1+(1/3)rt3
    Yeah sorry that was a typo I meant squareroot 3. Thank you for the help, I think I was making a silly mistake when simplifying it.
 
 
 
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