Question

prove that for any complex number z with |z| ≤ 2, there exist complex numbers z1 and z2 such that |z1| = |z2| = 1 and z1 + z2 = z

Answer 1

if z_1 and z_2 are represented by pointers or vectors with length one then you can see that the sum of z_1 and z_2 is on the circle. Pythagoras' Theorem might be helpful to prove it