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    I have to prove:
    sinx/(1+cosx) + (1-cosx)/sinx = 2tan(x/2)

    I'm up to 2sinx/1+cosx, but I don't know how to go from there.
    Any help would be appreciated! Thanks!
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    (Original post by кяя)
    I have to prove:
    sinx/(1+cosx) + (1-cosx)/sinx = 2tan(x/2)

    I'm up to 2sinx/1+cosx, but I don't know how to go from there.
    Any help would be appreciated! Thanks!


    sinA = 2sinA/2cosA/2

    since

    sin2A = 2sinAcosA


    similarly the cosine
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    (Original post by кяя)
    I'm up to 2sinx/1+cosx, but I don't know how to go from there
    You might want to write \sin x =  2 \sin \frac{x}{2} \cos \frac{x}{2} and \cos x = 2 \cos^2 \frac{x}{2} - 1
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    (Original post by TeeEm)
    sinA = 2sinA/2cosA/2

    since

    sin2A = 2sinAcosA


    similarly the cosine
    (Original post by Zacken)
    You might want to write \sin x =  2 \sin \frac{x}{2} \cos \frac{x}{2} and \cos x = 2 \cos^2 \frac{x}{2} - 1
    Thank you both of you so much!!
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    (Original post by кяя)
    Thank you both of you so much!!
    my pleasure
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    (Original post by кяя)
    Thank you both of you so much!!
    You're very welcome! :-)
 
 
 
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