To divide complex numbers in polar form, divide the r parts and subtract the angle parts. Or
r2(cosθ2 + i sinθ2) / r1(cosθ1 + i sinθ1) = r2/r1(cos(θ2−θ1) + i sin(θ2−θ1))
z1/z2
= 3/7 (cos(π/8-π/9) + i sin(π/8 - π/9))
= 3/7 (cos(π/72) + i sin(π/72))