You want to solve 4 tan x - 1 = - 3*tan(-x)
Now tan -x = - tan x
4 tan x - 1 = - 3*tan(-x)
=> 4*tan x - 1 = 3* tan x
=> tan x = 1
=> x = arc tan 1
=> x = pi/4 + n*pi and 5*pi/4
For the equation x = pi/4 + n*pi and x = 5*pi/4 + n*pi
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