∛(x-1) = 1-x I³ => x-1 = (1-x)³ I : (1-x) => -1 = (1-x)² => -1 = 1-2x+x² =>
x²-2x+2 = 0 => x₁ = [2+√(4-8)]/2 = 1+i
x₂ = 1-i