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    Prove that:
    (tanx*sinx)/(1-cosx)=1+(1)/(cosx)
    Many thanks
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    (Original post by orange8120)
    Prove that:
    (tanx*sinx)/(1-cosx)=1+(1)/(cosx)
    Many thanks
    Could you rewrite that please. The thing you wrote is not true.

    The chances are that (at C2) you need to write tan as sin/cos and cancel and possibly a bit more depending on what you are trying to prove
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    (Original post by nerak99)
    Could you rewrite that please. The thing you wrote is not true.

    The chances are that (at C2) you need to write tan as sin/cos and cancel and possibly a bit more depending on what you are trying to prove
    Are you sure?
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    Why not?
    ( sinx)^2=1-(cosx)^2=(1-cosx)*(1+cosx)

    (Original post by nerak99)
    Could you rewrite that please. The thing you wrote is not true.

    The chances are that (at C2) you need to write tan as sin/cos and cancel and possibly a bit more depending on what you are trying to prove
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    Tanx * sin x --------1
    ---------------- = 1 + --------
    1 - cosx. Cos x------cosx
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    (Original post by orange8120)
    Prove that:
    (tanx*sinx)/(1-cosx)=1+(1)/(cosx)
    Many thanks
    Hi. Some clues

    1. Try rewriting tanx as sinx/cosx
    2. Replace sin2x with 1 - cos2x
    3. Factorise with difference of two squares
    Spoiler:
    Show
    1. ((sinx/cosx)sinx) / (1 - cosx)

    2. sin2x / ((cosx(1 - cosx))

    3. (1 - cos2x) / (cosx(1 - cosx))

    4. (1 - cosx)(1 + cosx) / (cosx(1-cosx))

    5. (1 + cosx)/cosx

    6. (1/cosx + cosx/cosx) => 1 + 1/cosx
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    No I am wrong, I substituted in pi/4 and did 1+root 2 on the RHS instead of 1+1/(root 2). Sorry OP
 
 
 
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