I think this is asking for 3 ways of writing z = 4/(1+i√3)
1. Multiply numerator and denominator by 1 - i√3: 4(1 - i√3)/(1+3), so z = 1 - i√3
2. |z| = √(1+3) = 2, tan-1(-√3/1) = -pi/3: z = 2e-i*pi/3
3. eiθ = cos(θ) + i*sin(θ), so z = 2cos(pi/3) - 2i*sin(pi/3)
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