ExamBro
ExamBro
WBJEE · Maths · Straight Lines

Let \(A\) be the point \((0,4)\) in the xy-plane and let \(B\) be the point \((2 t, 0)\). Let \(L\) be the midpoint of \(A B\) and let the perpendicular bisector of \(A B\) meet the \(y\)-axis \(M\). Let \(N\) be the midpoint of LM. Then locus of \(N\) is

  1. A a circle
  2. B a parabola
  3. C a straight line
  4. D a hyperbola
Verified Solution

Answer & Solution

Correct Answer

(B) a parabola

Step-by-step Solution

Detailed explanation

Hint : Equation of LM \(\begin{aligned} & y-2=\frac{t}{2}(x-t) \\ & \Rightarrow M\left(0, \frac{4-t^2}{2}\right) \end{aligned}\) Midpoint of LM : N(h, k) \(\begin{aligned} & \Rightarrow \quad 2 h=t, 2 k=4-\frac{t^2}{2} \\ & \Rightarrow \quad x^2=2-y \end{aligned}\)
From WBJEE
Explore more questions on app