If the coordinates of A and B be (2,3,4) and (1,-2,1) respectively, then OA is _________ to OB, where O is the origin.
parallel
perpendicular
equal
not equal
If A,B,C, D are the points (2,3,-1), (5,2,3), (4,3,-5) and (-2, 1, -8) respectively. Then the projection of AB on CD is
2
4
6
8
The acute angle between two lines whose direction ratios are 2,3 6 and 1,2,2 respectively is
cos-1(21/20)
cos-1(19/20)
cos-1(21/22)
cos-1(20/21)
If α,β,γ be the angles which a line makes with the co-ordinate axes ,then
Sin2α + Cos2β + Sin2 γ=1
Cos2α + Cos2β + Cos2 γ=1
Sin2α + Sin2β + Sin 2γ=1
Cos2α + Cos2β + Sin2 γ=1
None of these
Line joining A (5,2,-3) to B (6,1,4) and C(-3,-2,-1) to D (-1,-4,11) are
none of these
For what value of x will the line through (4,1,2) and (5,x,O) be parallel to the line through (2,1,1) and (3,3,-1).
-3
3/2
3
If A(-3,2,4), B (2,5,-2) , C(1,-2,2) , D(4,2,3) are four given points, then angle θ between AB and CD is
60o
66o31'
75o 31'
120o 31'
P,Q,R,S are the points (-2,3,4) (-4,4,6) , (4,3,5) and (0,1,2). Projection of PQ is
right angles to RS
parallel to RS
equal to RS
The equation to the straight line passing through the points (4,-5,-2) and (-1,5,3) is
x-4/1=y+5/-2=z+2/-1
x+4/1=y-5/2=z-3/-1
x/-1=y/5=z/3
x/4=y/-5=z/-2