−98
−78
78
98
Correct answer is B
αβ+βα=α2+β2αβ
α+β=−ba; αβ=ca
α2+β2=(α+β)2−2(αβ)
From the equation, a = 2, b = -3, c =4
α+β=−(−3)2=32
αβ=42=2
α2+β2=(32)2−2(2))=94−4=−74
⟹αβ+βα=−742=−78
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