If z = log (tan x + tan y), then (sin 2x)∂z /∂x+(sin 2y) ∂z /∂y is equal to
A. 1
B. 2
C. 3
D. 4
The line y = x√2 + λ is a normal to the parabola y2 = 4ax, then λ =
A. 4√2
B. -4√2
C. 2√2
D. -2√2
The point on the parabola y = x2 + 7x + 2 closest to the line y = 3x – 3 is
A. (2,8)
B. (2,-8)
C. (-2,8)
D. (-2,-8)
If the lines 2x + 3y + 12 = 0,x – y + 4k = 0 are conjugate with respect to the parabola y2 = 8x then k =
A. 10
B. 7/2
C. -12
D. -2
I .thev locusv of the midpoints of chords of the parabola y2 = 4ax which substends a right angle at the vertex is y2 = 2a (x – 4a) II. the locus of midpoint of chords of the parabola y2 = 4ax which touch the circle X2 + y2 = a2 is (y2- 2ax)2 = a2 (y2 + 4a2)
A. Only I is true
B. Only II is true
C. Both I and II are true
D. Neither I nor II true
The equation of the common tangent to x2+ y2 = 8 and y2 = 16x is
A. Y = ± (x+ 2)
B. Y = ±(x + 4)
C. 2x + 3y + 36 = 0
D. 3x + 2y + 24 = 0
The length of the focal chord of the parbola y2 = 4ax which makes an angle θ with its axis is
A. 4a sin2 θ
B. 4a cos2 θ
C. 4 cos2 θ
D. 4a sec2 θ
L and L’are ends of the latus rectum of the parabola x2 = 6y. the equation of OL and OL’ where O is the origin is
A. X2 + 4y2 = 0
B. X2 – 4y2 = 0
C. X2 + 2y2 = 0
D. X2 – 2y2 = 0
The angle subtended at the focus by the normal chord of a parabola y2= 4ax at a point whose ordinate equal to abscisa is
A. Focus
B. Vertex
C. End of the latusrectum
D. None
If P (at21,2at1)and Q (at22,2at2),are variable points on the curve y2 = 4ax and PQ subtends a right angle at the vertex , than t1t2 =
A. -1
B. -2
C. -3
D. -4
The equation to the normal to the parabola y2 = 4x at (1,2) is
A. X + y -3 = 0
B. X + y +6 = 0
C. X – y + 5 = 0
D. X -y + 4= 0
Match the following Parabola Focus y2 –x – 2y + 2 = 0 (1,2) y2 – 8x – 4y – 4 = 0 (-2,5) x2 + 4x – 8y + 28 = 0 (1,-1) x2 – 2x – 8y – 23 = 0 (5/4,1)
A. A,b,c,d
B. B,c,a,d
C. D,a,b,c
D. B,d a,c
The locus of the poles of chords of the parabola y2 = 4ax, which subtend a right angle at the vertex is
A. X + a = 0
B. X + 2a = 0
C. X + 3a = 0
D. X + 4a = 0
If the equation of the parabola whose axis is parallel to x – axis and passing through (2,-1) (6,1) (3, -2) is ay2 + bx + cy + d = 0 then the ascending order of a,b,c,d is
A. A,b,c,d
B. B,c,a,d
C. c,a,b
D. b,a,c
if the focus is (1,-1) and the directrix is the line x + 2y – 9 = 0, the vertex of the parabola is at
A. (1,2)
B. (2,1)
C. (1,-2)
D. (2,-1)
I : If the points (2,-1), (5,k) are conjugate with respect to the parabola x2 = 8y then k = 7 II: If the lines 2x + 3y + 12 = 0,x – y + k = 0 are conjugate with respect to the parabola y2 = 8x then k = -12
A. Only I is true
B. Only II is true
C. Both I and II are true
D. Neither I nor II true
If the normal at (1,2) on the parabola again at the point (l2,2t), then the value of t is
A. 1
B. 3
C. -3
D. 1
If P is a point on the parabola y2 = 4ax such that the subtangent and subnormal at P are equal, then the coridinate of P are
A. (a,2a) or (a,-2a)
B. (2a,2√2a) or (2 - ,2√2A)
C. (4a,-4a) or (4a,4a)
D. None
The tangents to the parabola y2 = 4ax at p (t1) and Q (t2) intersect at R. the area of Δ PQR is
A. 1/2 a2 (t1- t2)2
B. 1/2 a1(t1-t2)
C. 1/2 a1 (t1-t2)3
D. None
The point on the parabola y2 = 36x whose oridinate is three times its abscissa is
A. (4, 12)
B. (-4, 12)
C. (4, -12)
D. (-4, -12)
the equation of the parabola whose axis is parallel to x –axis and passing through (- 2,1), (1,2), (-1,3) is
A. 5y2 + 2x – 21y + 20 = 0
B. 15y2 + 12x – 11y + 10 = 0
C. 18y2 – 12x + 21y + 56 = 0
D. 25y2 – 2x -65y + 120 = 0
The length of the latus rectum of the parabola x2 + 4x – 8y + 28 = 0 is
A. 16
B. 4
C. 2
D. 8
The equation of the axis of the parabola 3x2 – 9x + 5y -2 = 0 is
A. X – 2 =0
B. X – 1 = 0
C. X – 3 = 0
D. 2x – 3 = 0
The sub-tangent, ordinate and sub-normal to the parabola y2 = 4ax at a point ( diffferent from the origin ) are in
A. A.P.
B. H.P.
C. G.P.
D. None
The length of the chord intercepted bt the parabola y = x2 + 3x on the line x + y = 5 is
A. 3 √26
B. 2√26
C. 2√2
D. None
The equation of the axis of the parabola (y + 3)2 = 4(x – 2) is
A. X – 5 = 0
B. Y + 3 = 0
C. 2x – 1 = 0
D. Y – 1 = 0
Two straight lines are perpendicular to each other. One of them touches the parabola y2 = 4a (x + a) and the other touches y2 = 4b (x + b). the locus of the point of intersectionof the two lines is
A. X + a = 0
B. X + b = 0
C. X + a + b = 0
D. X – a – b = 0
The locus of the point of intersection of two tangents to the parabola y2 = 4ax which make the angle θ1 and θ2 with the axis so that cot θ1 + cos θ2 = k is
A. Kx – y = 0
B. Kx – a = 0
C. Y – ka = 0
D. X – ka = 0
The equation of the axis of the parabola (y + 3)2 = 4(x – 2) is
A. X – 5 = 0
B. Y + 3 = 0
C. 2x – 1 = 0
D. Y – 1 = 0
The equation of the tangent to the parabola y2 = 12x at (3, -6) is
A. X + y + 3 = 0
B. X + y + 1 = 0
C. X – y + 2a = 0
D. X + y + 1 = 0