In[]:=
CS:=SK/(v^2-1)Solve[{(SK*Cos[2*alpha]-CS-x)/(SK*Sin[2*alpha]-x)==(x-SK*Cos[alpha]-CS)/(x-SK*Sin[alpha])},alpha]
Out[]=
alpha ArcTan 2 2 SK 2 SK 2 v 2 SK 4 v ⋯59⋯ ⋯1⋯ 4 v 3 x 3 ( ⋯1⋯ 6 v 3 x 3 ( ⋯1⋯ 6 2 SK 2 SK 2 v 2 SK 4 v 2 x 2 v 2 x 4 v 2 x 6 v 2 x 3 x 2 v 3 x 4 v 3 x ⋯1⋯ 1 1 ⋯1⋯ ⋯1⋯ ⋯1⋯ ⋯1⋯ | |||||
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