Mathematics · Determinants

JEE Main 2024 — 6 April, Shift 2 — Question 29

If the system of equations

2x+7y+λz=32 \mathrm{x}+7 \mathrm{y}+\lambda \mathrm{z}=3

3x+2y+5z=43 x+2 y+5 z=4

x+μy+32z=−1x+\mu y+32 z=-1

has infinitely many solutions, then (λ−μ)(\lambda-\mu) is equal to \qquad

Answer: 38

Numerical answer — enter this value.

Step-by-step solution

D=D1=D2=D3=0\mathrm{D}=\mathrm{D}_{1}=\mathrm{D}_{2}=\mathrm{D}_{3}=0

D3=∣2733241μ−1∣=0{{D}_{3}}=\left| \begin{matrix}2 & 7 & 3 \\3 & 2 & 4 \\1 & \mu & -1 \\\end{matrix} \right|=0

⇒μ=−39\Rightarrow \mu =-39 D=∣27λ3251−3932∣=0\text{D}=\left| \begin{matrix}2 & 7 & \lambda \\3 & 2 & 5 \\1 & -39 & 32 \\\end{matrix} \right|=0

⇒λ=−1\Rightarrow \lambda =-1 λ−μ=38\lambda-\mu=38

Answer key and solution verified before publishing.

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Exam
JEE Main 2024
Subject
Mathematics
Chapter
Determinants
Topic
Consistency of Non-homogeneous system
If the system of equations 2 x +7 y +λ z =3 3 x+2 y+5 z=4 x+μ y+32… | JEE Main 2024 PYQ with Solution · DhiX AI