I'm having trouble proving these two trigonometric identities and there's no reference for answers. Also Wolfram Alpha just gives me "true". If you could possibly help that would be great. 1 + (cotx)(tany) = (sin(x+y))/((sinx)(cosy)) (1 + cosx)/sinx = cot (x/2)

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NotOP !!xbamUMLm3g1 Sun Dec 11 21:32:06 2011 No.4130137 [Reply] [Original]

I'm having trouble proving these two trigonometric identities and there's no reference for answers. Also Wolfram Alpha just gives me "true".

If you could possibly help that would be great.

1 + (cotx)(tany) = (sin(x+y))/((sinx)(cosy))

(1 + cosx)/sinx = cot (x/2)

>>	Anonymous Sun Dec 11 21:33:31 2011 No.4130145 First one: Take identity that has sin(x+y) in it. Divide each side by sin(x)cos(x) Second one: do something similarly fucking easy

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