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How do I prove this trig identity? watch

1. 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!
2. (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
3. (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 and
4. (Original post by TeeEm)
sinA = 2sinA/2cosA/2

since

sin2A = 2sinAcosA

similarly the cosine
(Original post by Zacken)
You might want to write and
Thank you both of you so much!!
5. (Original post by кяя)
Thank you both of you so much!!
my pleasure
6. (Original post by кяя)
Thank you both of you so much!!
You're very welcome! :-)

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