a·[1, 0, 2, 1] + b·[0, 0, 1, 1] + c·[-1, 1, 1, -1] + d·[1, 0, -1, 1] + e·[0, 1, -1, 0] = [0, 8, 1, 5] --> a = (e - 4)/3 ∧ b = 5 ∧ c = 8 - e ∧ d = 4·(7 - e)/3 --> a = -1 ∧ b = 5 ∧ c = 7 ∧ d = 8 für e = 1
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a·[1, 0, 2, 1] + b·[0, 0, 1, 1] = [0, 8, 1, 5] --> keine Lösung
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c·[-1, 1, 1, -1] + d·[1, 0, -1, 1] + e·[0, 1, -1, 0] = [0, 8, 1, 5] --> keine Lösung