Question

The chord of contact of tangents drawn from a point on the circle x2 +y2 = a2 to the circle x2 + y2 = b2 thouchese x2 + y2 = e2 find ab in.

Solution

Correct option is

G.P.

 

 be a point on the circle x2 + y2 = a2.   

Thus equation of chord x2 + y2 = a2 of contact of tangent drawn from  to the circle x2 + y2 = b2 is    

                                T = 0

  

This touches the circle x2 + y2 = e2     

So length of parallel from (0, 0) is equal to the radius

                    

                                        

 

SIMILAR QUESTIONS

Q1

Find the coordinates of the middle point of the chord which the circle x2y2 + 4x – 2y – 3 = 0 cut off the line x – y + 2 = 0.   

Q2

For what values of λ will the line y = 2x + λ be a tangent to the circle x2y2 = 5.

Q3

Find the equation of tangent to the circle x2 + y2 – 2ax = 0 at the point  

Q4

Find the equation of normal to the x2 + y2 = 2x which is parallel to x + 2y= 3.  

Q5

 

Find the equation of normal at the point (5, 6) to the circle;

x2 + y2 – 5x + 2y – 48 = 0   

Q6

Find the equation of tangent to the circle x2 + y2 = 16 drawn from the point (1, 4).

Q7

 

The angle between a pair of tangents from a point P to the circle

     x2 + y2 + 4x – 6y + 9 sin2α + 13 cos2α = 0 is 2α.

Find the equation of the lows of the point P.   

Q8

 

Find the length of tangents drawn from the point (3, – 4) to the circle

     2x2 + 2y2 – 7x – 9y – 30 = 0   

Q9

 

Find the condition that chord of contact of any external point (hk) to the circle x2 + y2 = a2 should subtend right angle at the centre of the circle. 

Q10

Find the middle point of the chord intercepted on line lx + my + n = 0 by the circle x2 + y2 = a2.