To multiply complex numbers in polar form: multiply the r parts and add the angle parts. Or
r1(cos θ1 + i sin θ1) × r2(cos θ2 + i sin θ2)
= r1r2(cos(θ1+θ2) + i sin(θ1+θ2))
so zw
=3*8(cos(π/9+π/12) + i sin(π/9+π/12))
=24(cos(7/36)π + i sin(7/35)π)
r1(cosθ1+isinθ1)*r2(cosθ2+isinθ2)
= r1*r2*(cos(θ1+θ2)+isin(θ1+θ2))
so zw
=3(cos(pi/9)+isin(pi/9))*8(cos(pi/12)+isin(pi/12))
=3*8*(cos(pi/9+pi/12)+isin(pi/9+pi/12))
=24(cos(7/36)pi+isin(7/35)pi)
