Application of DerivativeHard
Question
Let α, β, γ be the roots of the equation x3 + 3ax2 + 3bx + c = 0. If α, β, γ are in H.P. then β is equal to -
Options
A.- c/b
B.c/b
C.-a
D.a
Solution
α + β + γ = - 3a, αβγ = - c
αβ + βγ + γα = 3b ⇒
⇒
(∵ α, β, γ in H.P.)
αβ + βγ + γα = 3b ⇒
⇒
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