# Drawing phasor diagrams when x is the sum of two Cos terms

#### PhysicsKidd

If x= ACos(wt) + ACos(Wt), how do I draw a phasor diagram when t=2? Do I treat each cosine term as a vector, and then do vector addition? Thank you

w=4*pi and W=5*pi, by the way

#### ChipB

PHF Helper
At t = 2 the value of ACos(4 pi t ) is A, and the value of Acos(5 pi t ) is also A. So at t =2 the two phasors are aligned along the real axis, and so the vector addition gives a result of 2A along the real axis.