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    Q: Write down the value(s) of cotx in the following:

    3\frac{sinx}{cosx}=\frac{cosx}{s  inx}
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    whats tanx in terms of cosx and sinx?

    what then is cotx in terms of cosx and sinx?
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    I've got this far:

    3tanx = \frac{cosx}{sinx}



\frac{3}{cotx} = \frac{cosx}{sinx}



\frac{cotx}{3} = \frac{sinx}{cosx}



cotx = 3 \frac{sinx}{cosx}



cotx = 3tanx
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    i agree with that.

    now whats cotx in terms of tanx?
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    i got this so far 3 = cos^2 (x) / sin^2(x)

    is the answer square root of 3?
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    tanx = \frac{1}{cotx}

    That's where I'm stuck lol
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    tan (x)= cot (90-x)
    if that helps...
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    (Original post by darkness9999)
    i got this so far 3 = cos^2 (x) / sin^2(x)

    is the answer square root of 3?
    Yeah

    Can you show me your method? Thanks
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    (Original post by theworldwonders)
    tanx = \frac{1}{cotx}

    That's where I'm stuck lol
    so 3/cotx = cotx

    how did you solve equations like 3/u = u back in GCSE?
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    (Original post by Rocious)
    so 3/cotx = cotx

    how did you solve equations like 3/u = u back in GCSE?
    Erm, my memory is failing me

    Is it anything to do with rationalizing the denominator?
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    (Original post by theworldwonders)
    Yeah

    Can you show me your method? Thanks
    times both sides by cos x and sin x

    u will get then 3 sine^2 (x) = cos^2 (x)
    3 = cos^2 (x) / sin ^2 (x) = cos ^ 2 (x)
    so take the square root of both sides and ull get the answers
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    (Original post by theworldwonders)
    Erm, my memory is failing me

    Is it anything to do with rationalizing the denominator?
    if multiply both sides of 3/cotx = cotx by cotx

    you'll get

    3 = (cotx)^2

    and you can see why cotx = root3

    and you can also hopefully see the other solution
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    I would have transformed the original equation to:
    3tanx = cotx
    move the tanx over
    3 = cot^2x
    square root both sides,
    cotx = square root of 3
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    (Original post by Rocious)
    if multiply both sides of 3/cotx = cotx by cotx

    you'll get

    3 = (cotx)^2

    and you can see why cotx = root3

    and you can also hopefully see the other solution
    Ah, of course

    Thank you!
 
 
 
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