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    Hi so I'm finding this question difficult,

    Prove that:
    cosec(2x) - cot (2x) = tan x

    any help is appreciated, thanks
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    (Original post by 21deadpilots)
    Hi so I'm finding this question difficult,

    Prove that:
    cosec(2x) - cot (2x) = tan x

    any help is appreciated, thanks
    What have you tried?
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    (Original post by RDKGames)
    What have you tried?
    so I have tried changing cosec (2x) into 1/sin(2x) and cot(2x) into cos(2x)/sin(2x)

    Im not sure if i have to use the double angle formula or if its even needed :/
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    (Original post by 21deadpilots)
    so I have tried changing cosec (2x) into 1/sin(2x) and cot(2x) into cos(2x)/sin(2x)

    Im not sure if i have to use the double angle formula or if its even needed :/
    Yes you got it right. You can combine the two fractions too as they have the same denominator. Use double angle formulae and express 1 as \cos^2x + \sin^2 x and things should cancel down nicely.
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    (Original post by RDKGames)
    Yes you got it right. You can combine the two fractions too as they have the same denominator. Use double angle formulae and express 1 as \cos^2x + \sin^2 x and things should cancel down nicely.
    so which formula for cos(2x) should i use? and for the denominator I got 2sin (x)cos (x)
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    (Original post by 21deadpilots)
    so which formula for cos(2x) should i use? and for the denominator I got 2sin (x)cos (x)
    Preferably the one which involves both sine and cosine in order to cancel with the 1. Yeah the denominator is correct.
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    (Original post by RDKGames)
    Preferably the one which involves both sine and cosine in order to cancel with the 1. Yeah the denominator is correct.
    Ahh thanks so much!
 
 
 
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