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C3 Trigonometry help

Hi so I'm finding this question difficult,

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

any help is appreciated, thanks
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?
Reply 2
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 :/
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 cos2x+sin2x\cos^2x + \sin^2 x and things should cancel down nicely.
Reply 4
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 cos2x+sin2x\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)
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.
Reply 6
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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