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    Hey,

    Show that:

    tanx + cotx = 2cosec2x

    But the = is three lines (no button on the keyboard).

    Cheers
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    Write the LHS out in terms of sin and cos, and then put it over a common denominator
    i.e. a/b + b/a = (a^+b^2) /(ab)

    ....that gets you the answer.
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    Those three lines mean it is always equal to. Try turning cosec(2x) in something with only x (not 2x), using the sin double angle formula.
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    (Original post by TheDuck)
    Write the LHS out in terms of sin and cos, and then put it over a common denominator
    i.e. a/b + b/a = (a^+b^2) /(ab)

    ....that gets you the answer.
    Thanks, but it's: sinx/cosx + 1/tanx

    To get it in terms of sin/cos would I put the second part as 1/(sinx/cosx)? Not sure how that would work :confused:
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    (Original post by Waheyyyy)
    Thanks, but it's: sinx/cosx + 1/tanx

    To get it in terms of sin/cos would I put the second part as 1/(sinx/cosx)? Not sure how that would work :confused:
    yes thats correct ... so its cos/sin... multiply through and then ull get ur answer
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    \frac{sin(x)}{cos(x)}+\frac{cos(  x)}{sin(x)}=\frac{2}{sin(2x)}

    edit: darkness, you beat me to it. Damn you, LaTeX!
 
 
 
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