Can someone explain to me why xcosx - sinx = 0 when x = tanx? Thanks.
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Replace tanx with sinx/cosx and it comes right out.
Asked and answered in the other thread. Please do not double post. -Dan
Last edited by topsquark; November 6th 2012 at 05:30 PM.
Let x = tan x. Then x cos x - sin x = tan x * cos x - sin x = (sin x / cos x) * cos x - sin x = sin x - sin x = 0
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