Pair of Tangents, Chord of Contact and Chord with Midpoint of an Ellipse

IMPORTANT

Pair of Tangents, Chord of Contact and Chord with Midpoint of an Ellipse: Overview

This topic covers concepts, such as, Chord of Contact to an Ellipse, Length of Chord of Contact of an Ellipse, Pole and Polar with Respect to an Ellipse & Equation of the Polar of a Point with Respect to an Ellipse etc.

Important Questions on Pair of Tangents, Chord of Contact and Chord with Midpoint of an Ellipse

EASY
IMPORTANT

The line 2x+y=3 intersects the ellipse 4x2+y2=5 at two points. The tangents to the ellipse at these two points intersect at the point.

HARD
IMPORTANT

Let from a point Ah,k chord of contacts of the tangents are drawn to the ellipse x2+2y2=6 such that all these chords touch the ellipse x2+4y2=4, then the locus of the point A is

EASY
IMPORTANT

The equation of the chord having 1,1 as its mid-point with respect to the ellipse x225+y29=1, is 

HARD
IMPORTANT

 If tangent to parabola y2=4x intersect the ellipse x24+y29=1 at A and B and locus of point of intersection of tangents at A and B is a conic C, then

HARD
IMPORTANT

From a point O on the circle x2+y2=25, tangents OP and OQ are drawn to the ellipse x24+y21=1. If the locus of the mid point of the chord PQ describes the curve x2+y2=a2x2b+y212, thena3b=

HARD
IMPORTANT

If line x+y=1 is intersecting ellipse x23+y24=1 at two distinct points A and B, then point of intersection of tangents at A and B :

 

MEDIUM
IMPORTANT

The midpoint of a chord of the ellipse x2+4y2-2x+20y=0 is 2,-4. The equation of the chord is

HARD
IMPORTANT

AB is a diameter of x2+ 9y2=25 . The eccentric angle of A is π/6. Then the eccentric angle of B is -

HARD
IMPORTANT

If the point of intersection of the ellipses x2a2+y2b2=1 and x2α2+y2β2=1 be at the extremities of the conjugate diameters of the former, then -

HARD
IMPORTANT

Tangents are drawn from the points on the line x - y - 5=0 to x2+ 4y2=4 , then all the chords of contact pass through a fixed point, whose co-ordinates are -

HARD
IMPORTANT

The length of the diameter of the ellipse x225+y29=1 perpendicular to the asymptotes of the hyperbola x216-y29=1 passing through the first and third quadrant is

HARD
IMPORTANT

The chord of contact of the tangents drawn from (α,β) to an ellipse x2a2+y2b2=1 touches the circle x2+y2=c2, then the locus of (α,β) is

MEDIUM
IMPORTANT

The chord of contact of the tangents drawn from (α, β) to an ellipse x2a2+y2b2=1 touches the circle x2+y2=c2, then the locus of (α, β) is:

MEDIUM
IMPORTANT

Equation of chord of an ellipse x225+y29=1, whose mid point is (1, 1), is

HARD
IMPORTANT

If the chords of constant of tangents from two points (x1,y1) and (x2,y2) to the ellipse x2a2+y2b2=1 are at right angles, then x1x2y1y2 is equal to

HARD
IMPORTANT

If a variable tangent of the circle x2+y2=1 intersects the ellipse x2+2y2=4 at points P and Q, then the locus of the point of intersection of tangent at P and Q is

MEDIUM
IMPORTANT

If 2y=x and 3y+4x=0 are the equations of a pair of conjugate diameters of an ellipse, then the eccentricity of the ellipse is

HARD
IMPORTANT

If the chords of contact of tangents from two points x1,y1 & x2,y2 to the ellipse x2a2+y2b2=1 are at right angles then x1x2y1y2 is equal to

HARD
IMPORTANT

The area of the parallelogram formed by the tangents at the ends of conjugate diameters of an ellipse is