Pure Mathematics
posted by Kerry .
4) The roots of the equation z^2+2z+4=0 are denoted by α and β.
a) find α and β in the form re^iθ, giving the values of r and θ
b) Using de Moivre's Theorem, show that α^3=β^3.
c) find the exact value of αβ*+α*β

Pure Mathematics 
Steve
z = (2±√12)/2 = 1±i√3
or 6e^(i 2π/3) and 6e^(i 4π/3)
now the rest is easy...right?
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