Mathematics · Determinants

JEE Main 2024 — 8 April, Shift 2 — Question 3

If α≠a,β≠b,γ≠c\alpha \neq a, \beta \neq b, \gamma \neq c and ∣αbcaβcabγ∣=0\left| \begin{matrix}\alpha & b & c \\a & \beta & c \\a & b & \gamma \\\end{matrix} \right|=0, then aα−a+bβ−b+γγ−c\frac{\mathrm{a}}{\alpha-\mathrm{a}}+\frac{\mathrm{b}}{\beta-\mathrm{b}}+\frac{\gamma}{\gamma-\mathrm{c}} is equal to :

  1. Option A:

    2

  2. Option B:

    3

  3. Option C:

    0

    Correct
  4. Option D:

    1

Answer: C

Step-by-step solution

R1→R1−R2,R2→R2−R3\mathrm{R}_{1} \rightarrow \mathrm{R}_{1}-\mathrm{R}_{2}, \mathrm{R}_{2} \rightarrow \mathrm{R}_{2}-\mathrm{R}_{3}

∣α−ab−β00β−bc−γabγ∣=0\left| \begin{matrix}\alpha -\text{a} & \text{b}-\beta & 0 \\0 & \beta -\text{b} & \text{c}-\gamma \\\text{a} & \text{b} & \gamma \\\end{matrix} \right|=0

(α−a)(γ(β−b)−b(c−γ))−(b−β)(−a(c−γ))=0(\alpha-a)(\gamma(\beta-b)-b(c-\gamma))-(b-\beta)(-a(c-\gamma))=0

γ(α−a)(β−b)−b(α−a)(c−γ)+a(b−β)(c−γ)\gamma(\alpha-a)(\beta-b)-b(\alpha-a)(c-\gamma)+a(b-\beta)(c-\gamma)

γγ−c+bβ−b+aα−a=0\frac{\gamma}{\gamma-c}+\frac{b}{\beta-b}+\frac{a}{\alpha-a}=0

Answer key and solution verified before publishing.

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Exam
JEE Main 2024
Subject
Mathematics
Chapter
Determinants
Topic
Determinants
If α neq a, β neq b, γ neq c and begin matrix α & b & c \a & β & c \a… | JEE Main 2024 PYQ with Solution · DhiX AI