TestHub
TestHub

Mathematics - Hyperbola Question with Solution | TestHub

MathematicsHyperbolaTangent to hyperbolaMedium2 minPYQ_2015
MathematicsMediummultiple choice

Consider the hyperbolaH :x2-y2=1and a circle S with centerNx2, 0.Suppose that H and S touch each other at pointPx1, y1withx1>1 and y1>0.The common tangent to H and S at P intersects the x - axis at point M. If(l, m)is the centroid of the triangleΔPMN,then the correct expression(s) is(are)

Question diagram: Consider the hyperbola H : x 2 - y 2 = 1 and a circle S with

Options:(select one or more)

Answer:
A, B, D
Solution:



Equation of tangent at P on hyperbola.
xx1-yy1=1
PointM1x1 , 0
Equation of normal at P
xx1+yy1=2
Since(x2,0)satisfies its
x2=2x1
Centroidl,m x1+13x1, y13
dldx1=1-13x12
dmdy1=13
x12-y12=1
y1=x12-1
m=x12-13
dmdx1=x13x12-1
Alternative Method


l=3secθ+cosθ3
m=tanθ3=y13
dldx1=3secθtanθ-sinθ3secθtanθ=1-13 sec2 θ=1-13 x12
dmdx1=sec2θ3secθtanθ=cosec θ3=x13x12-1
dmdy1=13

Stream:JEE_ADVSubject:MathematicsTopic:HyperbolaSubtopic:Tangent to hyperbola
2mℹ️ Source: PYQ_2015

Doubts & Discussion

Loading discussions...