Question #fee42

1 Answer
Vinícius Ferraz
Dec 27, 2016

a + b in {-1, 0}

Explanation:

x^2 - Sx + P = 0

(1) S = a + b = -a
(2) P = ab = b \Rightarrow b (ab - b)/b = 0 \Rightarrow b(a - 1) = 0 \Rightarrow a = 1 or b = 0

if a = 1 then by (1), 1 + b = -1 \Rightarrow b = -2

if b = 0 then by (1), a + 0 = -a \Rightarrow 2a = 0 \Rightarrow a = 0

(a,b) = (1, -2) or (0,0)

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