ExamBro
ExamBro
JEE Mains · Maths · STD 11 - 10.2 parabola,ellipse,hyperbola

परवलयों \(y = x ^2\) तथा \(y =-( x -2)^2\) की एक उभयनिष्ठ स्पर्श रेखा का समीकरण है :

  1. A \(y=4(x-2)\)
  2. B \(y=4(x-1)\)
  3. C \(y=4(x+1)\)
  4. D \(y=4(x+2)\)
Verified Solution

Answer & Solution

Correct Answer

(B) \(y=4(x-1)\)

Step-by-step Solution

Detailed explanation

Equation of tangent of \(y = x ^{2}\) be \(t x=y+a t^{2}\) \(y=t x-\frac{t^{2}}{4}\) Solve with \(y=-(x-2)^{2}\) \(tx -\frac{ t ^{2}}{4}=-( x -2)^{2}\) \(x^{2}+x(t-4)-\frac{t^{2}}{4}+4=0\) \(D =0\) \(( t -4)^{2}-4 \cdot\left(4-\frac{ t ^{2}}{4}\right)=0\) \(t ^{2}-4 t =0\)…
Same subject
Explore more questions on app
From JEE Mains
Explore more questions on app