ExamBro
ExamBro
TS EAMCET · Maths · Pair of Lines

For \(\ell \in \mathbb{R}\), the equation \((2 \ell-3) \mathrm{x}^2+2 \ell \mathrm{xy}-\mathrm{y}^2=0\) represents a pair of distinct lines

  1. A only whən \(\ell=0\)
  2. B for all values of \(\ell \in(-3,1)\)
  3. C for all values of \(\ell \in \mathbb{R}-(0,1)\)
  4. D for all values of \(\ell \in \mathbb{R}-[-3,1]\)
Verified Solution

Answer & Solution

Correct Answer

(D) for all values of \(\ell \in \mathbb{R}-[-3,1]\)

Step-by-step Solution

Detailed explanation

\(a x^2+2 \mathrm{~h} x y+\mathrm{b} y^2=0\) represents distinct lines if \[ \begin{aligned} & h^2-a b>0 \therefore l^2+(2 l-3)>0 \\ & l^2+2 l-3>0 \\ & (l+3)(l-1)>0 \\ & \therefore l \in(-\infty,-3) \cup(1, \infty) \text { or } l \in \mathrm{R}-[-3,1] \end{aligned} \]