Pair of Tangents, Chord of Contact and Chord with Midpoint of a Circle

IMPORTANT

Pair of Tangents, Chord of Contact and Chord with Midpoint of a Circle: Overview

This topic covers concepts, such as Pair of Tangents from a Point to a Circle, Equations of Tangents from an External Point to a Circle, Length of Tangent to a Circle, Angle Subtended by a Circle at a Point, Chord of Contact to a Circle, etc.

Important Questions on Pair of Tangents, Chord of Contact and Chord with Midpoint of a Circle

MEDIUM
IMPORTANT

The angle between the tangents drawn from origin to the circle x-72+y+12=25 is equal to____.

HARD
IMPORTANT

Consider a circle S with centre at the origin and radius 4. Four circles A, B, C and D each with radius unity and centres -3,0, -1,0, 1,0 and 3,0 respectively are drawn. A chord PQ of the circle S touches the circle B and passes through the centre of the circle C. If the length of this chord can be expresses as x, find x.

HARD
IMPORTANT

The area of the triangle formed by the tangents from the point (4, 3) to the circle x 2 + y 2 =9 and the line joining their points of contact is

MEDIUM
IMPORTANT

The polars of two points A(5,7) and B(3,3) with respect to the circle x2+y2+2gx+2fy+c=0 intersect at C then find the polar of C with respect to the circle.

MEDIUM
IMPORTANT

The polars of two points A(1,3) and B(2,1) with respect to the circle x2+y2+2gx+2fy+c=0 intersect at C then find the polar of C with respect to the circle.

MEDIUM
IMPORTANT

Tangents are drawn from the point P1,-1 to the circle x2+y2-4x-6y-3=0 with centre CA and B are points of contact

The equation of the circle circumscribing the triangle formed by pair of tangent and corresponding chord of contact, is

MEDIUM
IMPORTANT

The area of triangle formed by pair of tangents drawn from 1,-1 to the circle x2+y2-4x-6y-3=0  and corresponding chord of contact, is 

EASY
IMPORTANT

Find the length of chord of contact drawn to the circle x2+y2=4 and the perpendicular distance of the chord from the origin is 1045

EASY
IMPORTANT

Find the length of chord of contact drawn to the circle x2+y2=10 and the perpendicular distance of the chord from the origin is 1045

MEDIUM
IMPORTANT

Identify the inverse point of (-2,2) with respect to the circle x2+y2=4 

MEDIUM
IMPORTANT

Identify the inverse point of (3,3) with respect to the circle x2+y2=9 

MEDIUM
IMPORTANT

Find the inverse point of (-3,3) with respect to the circle x2+y2=9 

MEDIUM
IMPORTANT

Find the inverse point of (2,2) with respect to the circle x2+y2=4 

EASY
IMPORTANT

If A and B are the point of contact of pair of tangents drawn from P6,8 on the circle x2+y2=16, then the circumradius of ΔOAB (where O being origin) is

MEDIUM
IMPORTANT

Tangents drawn from the point P1, 8 to the circle x2+y2-6x-4y-11=0 touch the circle at the points A and B. The equation of the circumcircle of the triangle PAB is

HARD
IMPORTANT

Tangents drawn from the point P1,8 to the circle x2+y2-6x-4y-11=0 touch the circle at the points A and B. The equation of the circumcircle of the triangle PAB is

HARD
IMPORTANT

The angle between a pair of tangents drawn from a point P to the circle x2+y2+4x-6y+9sin2α+13cos2α=0 is 2α.
The equation of the locus of point P is x2+y2+ax+by+c=0. Evaluate b2-ac.

HARD
IMPORTANT

A regular hexagon is formed by two equilateral triangles inscribed in the circle x2+y2=4. If S is the area of the hexagon (in sq. units), then find the greatest integer contained in S.

HARD
IMPORTANT

The polars of a point P with respect to two fixed circles meet in the point Q. Prove that the circle on PQ as diameter passes through two fixed points, and cuts both the given circles at right angles.

MEDIUM
IMPORTANT

The locus of the point of intersection of tangents to the circle x = a cosθ, y = a sinθ at a point whose parametric angles differ by π/3 is x2 + y2 = ka2. Find the value of 3k.