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    I'm not sure how to do this question, I got as far as rearranging the formula to tanx=3/root3

    How do you get to the step with tanx=1/root3

    Help would be appreciated.

    I've attached the question and the mark scheme answer
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    (Original post by smooo)
    I'm not sure how to do this question, I got as far as rearranging the formula to tanx=3/root3

    How do you get to the step with tanx=1/root3

    Help would be appreciated.

    I've attached the question and the mark scheme answer
    What is root 3 x root 3? Does that help?
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    (Original post by smooo)
    I'm not sure how to do this question, I got as far as rearranging the formula to tanx=3/root3

    How do you get to the step with tanx=1/root3

    Help would be appreciated.

    I've attached the question and the mark scheme answer
    Its root3/3 not 3/root3 and root3/3=1/root3
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    (Original post by veejn)
    Its root3/3 not 3/root3 and root3/3=1/root3
    Uhm, your intial post is wrong.

    You have 3\tan x - \sqrt{3} = 0. Add \sqrt{3} to both sides: 3\tan x = \sqrt{3}.

    Now divide throughout by 3 to get \tan x = \frac{\sqrt{3}}{3} \neq \frac{3}{\sqrt{3}}.

    Anyways, we have \tan x = \frac{\sqrt{3}}{3}.

    Now two ways to think about this:

    1) indices rules: \frac{\sqrt{3}}{3} = \frac{3^{1/2}}{3^1} = 3^{1/2 - 1} = 3^{-1/2} = \frac{1}{3^{1/2}}=  \frac{1}{\sqrt{3}}

    2) multiply top and bottom by \sqrt{3}: \frac{\sqrt{3}\sqrt{3}}{3\sqrt{3  }} = \frac{3}{3\sqrt{3}} = \frac{1}{\sqrt{3}}
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    (Original post by Zacken)
    Uhm, your intial post is wrong.

    You have 3\tan x - \sqrt{3} = 0. Add \sqrt{3} to both sides: 3\tan x = \sqrt{3}.

    Now divide throughout by 3 to get \tan x = \frac{\sqrt{3}}{3} \neq \frac{3}{\sqrt{3}}.

    Anyways, we have \tan x = \frac{\sqrt{3}}{3}.

    Now two ways to think about this:

    1) indices rules: \frac{\sqrt{3}}{3} = \frac{3^{1/2}}{3^1} = 3^{1/2 - 1} = 3^{-1/2} = \frac{1}{3^{1/2}}=  \frac{1}{\sqrt{3}}

    2) multiply top and bottom by \sqrt{3}: \frac{\sqrt{3}\sqrt{3}}{3\sqrt{3  }} = \frac{3}{3\sqrt{3}} = \frac{1}{\sqrt{3}}
    Ah ok I get it now that you have to use indices, thank you.
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    (Original post by smooo)
    Ah ok I get it now that you have to use indices, thank you.
    You don't have to use indices, I've given you two different ways to think about it. But sure, no problem.
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    (Original post by Zacken)
    You don't have to use indices, I've given you two different ways to think about it. But sure, no problem.
    To be fair, if you plugged in root 3 / 3 or 1 / root 3 into your calculator you'd still get the same solutions
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    (Original post by Rhy)
    To be fair, if you plugged in root 3 / 3 or 1 / root 3 into your calculator you'd still get the same solutions
    Yes, that was the point of my post, demonstrating their equivalency.
 
 
 
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