find limit x->pi [(x-pi).cotx]. I am stuck at x-pi/tanx
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Have you tried L'Hôpital's rule?
no. But I found the answer.
tanx=tan(x-pi) and this makes 1.
Originally Posted by kastamonu find limit x->pi [(x-pi).cotx]. I am stuck at x-pi/tanx
Many Thanks. I found it by using tanx/x=1
`tan (a - b)` = `(tan a - tan b)/(1 + tan a*tan b)` `tan (x - pi )` = `(tan x - tan pi)/(1 + tan x*tan pi)` tan pi = sin pi/cos pi = 0/-1 = 0` `tan (x - pi) = (tan x - 0)/(1 + tan x*0)` `tan(x - pi) = tan x`
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