The shortest distance from the plane 12x + y + 3z = 327 to the sphere x2 + y2 + z2 + 4x - 2y - 6z = 155 is
13
26
39
If the vertices of a· triangle are A(0, 4, 1), B(2, 3, - 1) and C(4, 5, 0), then the orthocentre of ABC, is
(4, 5, 0)
(2, 3, - 1)
(- 2, 3, - 1)
(2, 0, 2)
The normals at three points· P,Q and R of the parabola y2 = 4ax meet at (h, k). The centroid of the PQR lies on
x = 0
y = 0
x = - a
y = a
A tower AB leans towards West making an angle with the vertical. The angular elevation of B, the top most point of the tower is as observed from a point C due East of A at a distance 'd' from A. If the angular elevation of B from a point D due East of C at a distance 2d from C is r, then 2 can be given as
The number of integral points (integral points means both the coordinates should be integer) exactly in the interior of the triangle with vertices (0, 0), (0, 21) and (21, 0) is
133
190
233
105
The sides AB, BC and CA of a have respectively 3, 4 and 5 points lying on them. number of triangles that can be constructed using these points as vertices is
205
220
210
None of these
P is a fixed point (a, a, a) on a line through the origin is equally inclined to the axes, then any plane through P perpendicular to Op, makes intercepts on the axes, the sum of whose reciprocal is equal to
a
None of these
The tangent at (1, 7) to the curve x2 = y - 6 touches the circle x2 + y2 + 16x + 12y + c = 0 at
(6, 7)
(- 6, 7)
(6, - 7)
(- 6, - 7)
In an equilateral triangle, the inradius, circumradius and one of the exradii are in the ratio
2 : 3 : 5
1 : 2 : 3
1 : 3 : 7
3 : 7 : 9