tan(x) = -a
tan(3*x) = a
tan(3*x) = a
-1
-2.35619449019234
-1
0.785398163397448
0
0
0
3.14159265358979
1
-0.785398163397448
1
2.35619449019234
a1 = -1.0 x1 = -2.356194490192345
a2 = 1.0 x2 = -10.21017612416683
a3 = 2.646977960169689e-23 x3 = 6.283185307179586
a4 = -1.0 x4 = 10.21017612416683
a5 = 1.0 x5 = 2.356194490192345
a6 = -2.646977960169689e-23 x6 = -6.283185307179586
a6 = -2.646977960169689e-23 x6 = -6.283185307179586