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    Tan 2x = tan x
    between 0 and two pi

    pls show full steps I ended up with

    (tan x)(sec x) = 0

    I can get solution for tan, but I don't know how to work out for sec X ?? ideas

    Answers are 0, 3.14 , 6.28 in radians
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    tan2x = 2tanx/(1-tan²x)

    => 2tanx/(1-tan²x) = tanx
    2tanx = tanx - tan³x
    tan³x + tanx = 0
    tanx(tan²x+1) = 0
    tanx.sec²x = 0

    sec²x = 1/cos²x, so sec²x = 0 has no solutions.

    tanx = 0
    x = 0 , pi , 2pi (or 3.14 and 6.28, if you wanna decimalise it)
 
 
 
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Updated: June 17, 2005
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