Verified Solution • 2025–26 Session moderate

QJEEM21Mafcba: JEE Main 2021 Mathematics - Class 12 JEEM21Mafcba Solution: Let α , β , γ be the real roots of the equation, x 3 + ax 2 +…

Let α, β, γ be the real roots of the equation, x3 + ax2 + bx + c = 0, (a, b, c ∈ R and a, b ≠ 0). If the system of equations (in u, v, w) given by αu + βv + γw = 0, βu + γv + αw = 0; γu + αv + βw = 0 has non-trivial solution, then the value of a2b is

Multiple Choice Options

  • A 5
  • B 3
  • C 1
  • D 0

Step-by-Step Verified Solution

x3 + ax2 + bx + c = 0

Roots are α, β, γ.

For non-trivial solutions,

|αβγβγαγαβ|=0

⇒ α3+β3+γ3−3αβγ=0

⇒ (α+β+γ)[(α+β+α)2−3(∑αβ)]=0

⇒ (−a)[a2−3b]=0

⇒ a2=3b (∵ a ≠ 0)

⇒a2b=3

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