Three Dimension...

The locus of a point which moves so that the difference of the squares of its distances from two given points is constant, is a:

The radius of the sphere through the points ( 4 ,3 , 0 ) , ( 0 , 4 , 3 ) ,( 0 , 5 , 0 ) and ( 4 , 0 , 3 ) is

The direction ratios of normal to the plane through (1, 0, 0) and (0, 1, 0), which makes an angle π/4 with the plane x + y = 3, are

If the direction cosines of a straight line are < k , k , k > , then what will be the value of k

The angle between the lines x = 1, y = 2 and y = 1, z = 0 is

the numbers 3, 4 , 5 can be

The cosine of the angle between any two diagonals of a cube

The shortest distance from the plane 12x + 4y + 3z = 327 to the sphere x² + y² + z² + 4x – 2y – 6z = 155 is: