Search All of the Math Forum:
Views expressed in these public forums are not endorsed by
Drexel University or The Math Forum.



Re: sin(2x)=tanx, can't find all solutions
Posted:
Sep 22, 2006 2:02 AM


Denote tan x = t Given equation can be written as 2t /(1+t^2) = t t(1 + t^2 2) = 0 t = 0 or t = 1 or t = 1 tan x = 0 or tan x = 1 or tan x = 1 x = n pi or x = n pi + (pi/4) or x = n pi  (pi/4) where n 1s any integer.
Vijayaprasad
> I'm trying to solve sin(2x)=tanx, but I can't seem to > find all the > solutions. This is what I've got: > sin2x=tanx > 2sinxcosx=sinx/cosx > cos^2x=1/2 > cosx=+1/sqrt2 > x=+pi/4+pi2k (k=0, +1, +2...) > x=+3pi/4+pi2k > But there are more solutions than these, for example > x=pi. How do I find > them? > > /Johan



