ExamBro
ExamBro
COMEDK · Maths · 27. Application of Derivatives

If tangent to the curve \(x=a t^{2}, y=2 a t\) is perpendicular to \(X\)-axis, then its point of contact is

  1. A \((a, a)\)
  2. B \((0, a)\)
  3. C \((0,0)\)
  4. D \((a, 0)\)
Verified Solution

Answer & Solution

Correct Answer

(C) \((0,0)\)

Step-by-step Solution

Detailed explanation

We have, \[ x=a t^{2}, y=2 a t \] Now, \(\quad \frac{d x}{d t}=2 a t, \frac{d y}{d t}=2 a\) \[ \therefore \quad \frac{d y}{d x}=\frac{d y / d t}{d x / d t}=\frac{2 a}{2 a t}=\frac{1}{t} \] Since, tangent is perpendicular to \(X\)-axis, then \(\frac{d y}{d x}=\frac{1}{0}\)…