HARD
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Let 3x-y-8=0 be the equation of tangent to a parabola at the point 7,13. If the focus of the parabola is at -1,-1, then the equation of its directrix is

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Important Questions on Parabola

MEDIUM
If two tangents to the parabola y2=8x meet the tangent at its vertex in M and N such that MN=4, then the locus of the point of intersection of those two tangents is
HARD
Tangent and normal are drawn at P16,16 on the parabola y2=16x, which intersect the axis of the parabola at A &B, respectively. If C is the center of the circle through the points P, A &B and CPB=θ, then a value of tanθ is:
HARD
Let P be a point on the parabola, y2=12x and N be the foot of the perpendicular drawn from P , on the axis of the parabola. A line is now drawn through the mid-point M of PN, parallel to its axis which meets the parabola at Q. If the y-intercept of the line NQ is 43, then :
MEDIUM
Suppose OABC is a rectangle in the xy-plane where O is the origin and A,B lie on the parabola y=x2. Then C must lie on the curve-
HARD
Let E denote the parabola y2=8x. Let P=-2,4, and let Q and Q' be two distinct points on E such that the lines PQ and PQ' are tangents to E. Let F be the focus of E. Then which of the following statements is (are) TRUE?
MEDIUM
The shortest distance between the line y=x and the curve y2=x2 is
HARD
Let P and Q be distinct points on the parabola y2=2x  such that a circle with PQ as diameter passes through the vertex O of the parabola. If P lies in the first quadrant and the area of the triangle ΔOPQ is 32 sq. units, then which of the following is (are) the coordinates of P?
HARD
The shortest distance between the line x-y=1 and the curve x2=2y is:
MEDIUM
The focus of the parabola y=2 x 2 +x is
HARD
Let P be the point on the parabola y2=4x which is at the shortest distance from the center S of the circle x2+y2-4x-16y+64=0. Let Q be the point on the circle dividing the line segment SP internally. Then -
HARD
The length of the chord of the parabola x2=4y having equation x-2y+42=0 is
EASY
If the three normals drawn to the parabola, y2=2x pass through the point a,0, a0, then a must be greater than :
HARD
If the tangents and normals at the extremities of a focal chord of a parabola intersect at x1,y1 and x2,y2 respectively, then
MEDIUM
Let A1,2, B4,-4, C2,22 be points on the parabola y2=4x. If α and β respectively represent the area of ΔABC and the area of the triangle formed by the tangents at A, B, C to the above parabola, then αβ=
MEDIUM
Prove that the semi-latus rectum is a harmonic mean between the segments of any focal chord of a parabola.
MEDIUM
The coordinates of focus of a parabola which touches the lines x=0, y=0, x+y=1 & y=x-2 are
HARD
Let a focal chord of parabola y2=16x cuts it at points f, g and h, k. Then fh is equal to
HARD
If P(at2, 2at) be one end of a focal chord of the parabola y2=4ax, then the length of the chord is
MEDIUM
Find the points on the parabola y2=4ax, (a>0) for which length of the normal is equal to twice of length of the subtangent.
HARD

The set of values of a for which at least one tangent to the parabola y2=4ax becomes normal to the circle x2+y2- 2ax- 4ay+3a2=0, is (where a is a real number)