Get Answers to all your Questions

header-bg qa

The number of real values of \lambda, such that the system of linear equations

\mathrm{2 x-3 y+5 z=9} \\

\mathrm{x+3 y-z=-18} \\

\mathrm{3 x-y+\left(\lambda^{2}-|\lambda|\right) z=16 }

has no solutions, is

Option: 1

0


Option: 2

1


Option: 3

2


Option: 4

4


Answers (1)

best_answer

For no solution

\mathrm{\Delta=0} \\

\mathrm{\left|\begin{array}{ccc} 2 & -3 & 5 \\ 1 & 3 & -1 \\ 3 & -1 & \lambda^{2}-1 \lambda \mid \end{array}\right|=0 }

\mathrm{\Rightarrow 2\left(3 \lambda^{2}-3|\lambda|-1\right)+3\left(\lambda^{2}-|\lambda|+3\right)+5(-1-9)=0} \\

\mathrm{\Rightarrow 9 \lambda^{2}-9|\lambda|-43=0} \\

\mathrm{ \text { As } f(0)<0}

\Rightarrow \left |\lambda \right| has a positive ad a negative root,which gives z real values of \lambda.

Hence correct option is 3

Posted by

Sayak

View full answer

JEE Main high-scoring chapters and topics

Study 40% syllabus and score up to 100% marks in JEE