Show that the stator magnetic field of a three-phase generator has a constant magnitude and rotates with constant angular frequency. You can assume that the magnetic fields produced by the stator windings A, B,and C, are B_A = ê_A sinωt, B_B = ê_B sin(ωt − 2π/3), and B_C = ê_C sin(ωt − 4π/3), where ê_A,B,C are unit vectors rotated by 120^◦ with respect to one another. if you are comfortable with manipulating complex numbers,this may be the simplest approach to take, though the problem can be solved without complex numbers.