Let S = {(x,y)∈R2:1+ry2−1−rx2};r=±1. Then S represents :
02Medium74×since 2004Q3751
Let the length of the latus rectum of an ellipse with its major axis along x-axis and centre at the origin, be 8. If the distance between the foci of this ellipse is equal to the length of its minor axis, then which one of the following points lies on it?
03Medium74×since 2004Q3752
Let S and S' be the foci of an ellipse and B be any one of the extremities of its minor axis. If ΔS'BS is a right angled triangle with right angle at B and area (ΔS'BS) = 8 sq. units, then the length of a latus rectum of the ellipse is :
04Medium74×since 2004Q3748
The eccentricity of an ellipse having centre at the origin, axes along the co-ordinate
axes and passing through the points (4, −1) and (−2, 2) is :
05Medium74×since 2004Q3753
In an ellipse, with centre at the origin, if the
difference of the lengths of major axis and minor
axis is 10 and one of the foci is at (0,53), then
the length of its latus rectum is :
06Medium74×since 2004Q3715
Let an ellipse E:a2x2+b2y2=1, a2>b2, passes through (23,1) and has eccentricity 31. If a circle, centered at focus F(α, 0), α > 0, of E and radius 32, intersects E at two points P and Q, then PQ² is equal to :
07Medium74×since 2004Q3716
The line y = x + 1 meets the ellipse 4x2+2y2=1 at two points P and Q. If r is the radius of the circle with PQ as diameter then (3r)² is equal to :
08Hard74×since 2004Q3717
Consider ellipses Ek:kx2+k2y2=1,k=1,2,…,20. Let Ck be the circle which touches the four chords joining the end points (one on minor axis and another on major axis) of the ellipse Ek. If rk is the radius of the circle Ck, then the value of \sum_\limits{k=1}^{20} \frac{1}{r_{k}^{2}} is :
09Medium74×since 2004Q3718
The length of the chord of the ellipse 25x2+16y2=1, whose mid point is (1,52), is equal to :
10Hard74×since 2004Q3719
STATEMENT-1 : An equation of a common tangent to the parabola y2=163x and the ellipse 2x2+y2=4 is y=2x+23
STATEMENT-2 :If line y=mx+m43,(m=0) is a common tangent to the parabola y2=163xand the ellipse 2x2+y2=4, then m satisfies m4+2m2=24
11Medium74×since 2004Q3720
If the tangent to the parabola y² = x at a point
(α, β), (β > 0) is also a tangent to the ellipse,
x² + 2y² = 1, then α is equal to :
12Easy74×since 2004Q3721
If m is the slope of a common tangent to the curves 16x2+9y2=1 and x2+y2=12, then 12m2 is equal to :
13Medium74×since 2004Q3722
Let a circle of radius 4 be concentric to the ellipse 15x2+19y2=285. Then the common tangents are inclined to the minor axis of the ellipse at the angle :
14Medium74×since 2004Q3723
The locus of the foot of perpendicular drawn from the centre of the ellipse x2+3y2=6 on any tangent to it is :
15Easy74×since 2004Q3724
The locus of mid-points of the line segments joining (−3, −5) and the points on the ellipse 4x2+9y2=1 is :
16Medium74×since 2004Q3725
The locus of the mid point of the line segment joining the point (4, 3) and the points on the ellipse x2+2y2=4 is an ellipse with eccentricity :
17Hard74×since 2004Q3726
Let P be a point on the ellipse 9x2+4y2=1. Let the line passing through P and parallel to y-axis meet the circle x2+y2=9 at point Q such that P and Q are on the same side of the x-axis. Then, the eccentricity of the locus of the point R on PQ such that PR:RQ=4:3 as P moves on the ellipse, is :
18Medium74×since 2004Q3727
The eccentricity of an ellipse whose centre is at the origin is 21. If one of its directrices is x = – 4, then the
equation of the normal to it at (1,23) is :
19Easy74×since 2004Q3728
The tangent and normal to the ellipse 3x²
+ 5y²
= 32 at the point P(2, 2) meet the x-axis at Q and R,
respectively. Then the area (in sq. units) of the triangle PQR is :
20Medium74×since 2004Q3729
If the normal to the ellipse 3x²
+ 4y²
= 12 at a point P on it is parallel to the line, 2x + y = 4 and the tangent
to the ellipse at P passes through Q(4,4) then PQ is equal to :