Processing math: 100%

CBSE Questions for Class 12 Commerce Maths Three Dimensional Geometry Quiz 2 - MCQExams.com

The projection of the join of the two points (1,4,5),(6,7,2) on the line whose d.s's are (4,5,6) is
  • 1777
  • 76
  • 21
  • 79
If the d.cs of two lines are connected by the equations l+m+n=0,l2+m2n2=0, then angle between the lines is
  • π3
  • π4
  • π6
  • π2
The direction cosines of a line which is equally inclined to axes, is given by
  • ±13
  • ±13
  • 1
  • 0
The equation of the plane passing through (2,3,1) and is normal to the line joining the points (3,4,1) and (2,1,5) is given by
  • x+5y6z+19=0
  • x5y+6z19=0
  • x+5y+6z+19=0
  • x5y6z19=0
The equation of the plane containing the line 
r=ˆi+ˆj+t(2ˆi+ˆj+4ˆk), is
  • r.(ˆi+2ˆjˆk)=3
  • r.(ˆi+2ˆjˆk)=6
  • r.(ˆi2ˆj+ˆk)=3
  • None of these
A line passes through the points (6,7,1) and (2,3,1). The direction cosines of the line so directed that the angle made by it with the positive direction of x-axis is acute, is?
  • 23,23,13
  • 23,23,13
  • 23,23,13
  • 23,23,13
If P be the point (2,6,3) then the equation of the plane trough P, at right angles to OP, where  O is the origin is
  • 2x+6y+3z=7
  • 2x6y+3z=7
  • 2x+6y3z=49
  • 2x+6y+3z=49
The equation of the plane passing through (a,b,c) and parallel to the plane r.(ˆi+ˆj+ˆk)=2 is,
  • x+y+z=1
  • ax+by+cz=1
  • x+y+z=a+b+c
  • None of these
Angle between the lines 3x=6y=2z and 3x+2y+z5=0=x+y2z3 is?
  • π6
  • π3
  • π4
  • π2
The points i+j+k,i+2j,2i+2j+k,2i+3j+2k are
  • collinear
  • coplanar but not collinear
  • non-coplanar
  • none
If the dr's the line are (1+λ,1λ,2) and it makes an angle 60o with the Y-axis then λ is
  • 1±3
  • 4±5
  • 2±23
  • 2±5
The line joining the points (2,1,8) and (a,b,c) is parallel to the line whose direction ratios are 6,2,3. The value of a,b,c are
  • (4,3,5)
  • (1,2,13/2)
  • (10,5,2)
  • (5,3,4)
If a line has the direction ratio 18,12,4, then its direction cosines are:
  • 911, 611, 211
  • 913, 613, 213
  • 97, 67, 27
  • None of these
Equation of a line passing through the point ˆi+ˆjˆk and parallel to the vector 2ˆi+ˆj+2ˆk is
  • r=(1+2t)ˆi+(1+t)ˆj+(1+2t)ˆk
  • r=(1+2t)ˆi+(1+t)ˆj+(2t1)ˆk
  • r=(2t1)ˆi+(1+t)ˆj+(2t+1)ˆk
  • r=(12t)ˆi+(1+t)ˆi+(2t+1)ˆk
A line with positive direction cosines passes through the point P(2,1,2) and makes equal angles with the coordinate axes. The line meets the plane 2x+y+z=9 at point Q. The length of the line segment PQ equals
  • 1
  • 2
  • 3
  • 2
Assertion (A): The points with position vectors ¯a,¯b,¯c are collinear if 2¯a7¯b+5¯c=0.
Reason (R): The points with position vectors ¯a,¯b,¯c are collinear if l¯a+m¯b+n¯c=¯0.
  • Both A and R are true and R is correct reason of A
  • Both A and R are true and R is not correct reason of A
  • A is true R is false
  • A is false R is true
If the points with position vectors 60ˆi+3ˆj,40ˆi8ˆj and aˆi52ˆj are collinear then a is equal to
  • 40
  • 20
  • 20
  • 40
The three points ABC have position vectors (1,x,3),(3,4,7) and (y,2,5) are collinear then (x,y)=
  • (2,3)
  • (2,3)
  • (2,3)
  • (2,3)
If ¯a and ¯b are two non-collinear vectors, then the points l1¯a+m1¯b, l2¯a+m2¯b and l3¯a+m3¯b are collinear if
  • l1(m2m3)=0
  • l1(m1m3)=0
  • l1(m1+m3)=0
  • l1(m2+m3)=0
A line makes an angle α,β,γ with the X,Y,Z axes. Then sin2α+sin2β+sin2γ=
  • 1
  • 2
  • 32
  • 4
The vectors 2ˆi+3ˆj;5ˆi+6ˆj;8ˆi+λˆj have their initial points at (1,1). The value of  λ so that the vectors terminate on one straight line is
  • 0
  • 3
  • 6
  • 9
The position vectors of three points are 2ab+3c,a2b+λc and μa5b, where a,b,c are non-coplanar vectors. The points are coliinear when
  • λ=2,μ=94
  • λ=94,μ=2
  • λ=94,μ=2
  • None of these
The line passing through the points 10ˆi+3ˆj, 12ˆi+5ˆj also passes through the point aˆi+11ˆj, then a=
  • 8
  • 4
  • 18
  • 12
If the points (h,3,4),(0,7,10) and (1,k,3) are collinear, then h+k is
  • 4
  • 0
  • 4
  • 14
The point collinear with (1,2,3) and (2,0,0) among the following is
  • (0,4,6)
  • (0,4,5)
  • (0,4,6)
  • (0,4,6)
If the points whose position vectors are 2¯i+¯j+¯k, 6¯i¯j+2¯k and 14¯i5¯j+p¯k are collinear then the value of p is
  • 2
  • 4
  • 6
  • 8
The points with position vectors a+b,ab and a+λb are collinear for
  • Only integrals values of λ
  • No value of λ
  • All real values of λ
  • Only rational values of λ
If A=(1,2,3),B=(2,10,1), Q are collinear points and Qx=1, then Qz=
  • 3
  • 7
  • 14
  • 7
If PQR are the three points with respective position vectors ˆi+ˆj, ˆiˆj and aˆi+bˆj+cˆk, then the points PQR are collinear if
  • a=b=c=1
  • a=b=c=0
  • a=1, b,c in R
  • a=1,c=0, bR
Find the angle between the two lines having direction ratio (1,1,2) and ((31),(31),4).
  • π3
  • π2
  • π6
  • None of these
The three points whose position vectors are ¯i+2¯j+3¯k, 3¯i+4¯j+7¯k, and  3¯i2¯j5¯k
  • Form the vertices of an equilateral triangle
  • Form the vertices of an right angled triangle
  • Are collinear
  • Form the vertices of an isosceles triangle
Find the angle between the lines r=3i+2j4k+λ(i+2j+2k) and r=(5j2k)+μ(3i+2j+6k) 
  • θ=cos1(1921)
  • θ=sin1(1921)
  • θ=cos1(2021)
  • None of these
If a,b,c are the position vectors of points lie on a line, then a×b+b×c+c×a=
  • 0
  • b
  • 1
  • a
The product of the d.r's of a line perpendicular to the plane passing through the points (4,0,0),(0,2,0) and (1,0,1) is
  • 6
  • 2
  • 0
  • 1
The d.r's of the line of intersection of the planes x+y+z1 =0 and 2x+3y+4z7 =0 are
  • 1,2,3
  • 2,1,3
  • 4,2,6
  • 1,2,1
The d.c's of the normal to the plane 2xy+2z+5=0 are 
  • (3,2,6)
  • (27,37,67)

  • (3727,67)

  • (2313,23)

The plane which passes through the point (1,0,6) and perpendicular to the line whose direction ratios is (6,20,1) also passes through the point:
  • (1,1,26)
  • (0,0,0)
  • (2,1,32)
  • (1,1,1)
If R(a+2,a+3,a+4) divides the line segment joining P(2,3,4) and Q(4,5,6) in the ratio 3:2, then the value of the parameter which represents a is
  • 3
  • 2
  • 6
  • 1
lf the equation of the plane perpendicular to the z -axis and passing through the point (2,3,4) is ax+by+cz=d then a+b+cd=
  • 4
  • 34
  • 3
  • 14
The equation to the plane bisecting the line segment joining (3,3,2),(9,5,4) and perpendicular to the line segment is
  • xy+4Z13=0
  • 2x2y+7z23=0
  • x7y+2Z1=0
  • 6x+y+z25=0
The direction ratios of a normal to the plane through (1, 0, 0), (0, 1, 0) which makes an angle of π4 with the plane x+y=3 are
  • 1, 2, 1
  • 1, 1,  2
  • 1, 1, 2
  • 2, 1, 1
Equation of the plane through the mid-point of the join of A(4,5,10) and B(1,2,1) and perpendicular to AB is
  • r.(5i+3j11k)+1352=0
  • r.(5i+3j11k)=1352
  • r.(32ˆi+72ˆj92ˆk)=5ˆi+3ˆj11ˆk
  • r.(5i+3j11k)+1852=0
If (2,3,1) is the foot of the perpendicular from (4,2,1) to a plane, then the equation of that plane is ax+by+cz=d. Then a+d is
  • 3
  • 1
  • 2
  • 2
The product of the d.cs of the line which makes equal angles with ox,oy,oz is
  • 1
  • 3
  • 133
  • 13

lf θ is the angle  between two lines whose d.cs are l1,m1,n1 and l2,m2,n2, then

Σ(l1+l2)24cos2(θ2)+Σ(lIl2)24sin2(θ2)=

  • 1
  • 0
  • 1
  • 2
lf a line makes angles π12,5π12 with OY,OZ respectively where O=(0,0,0), then the angle made by that line with OX is
  • 45o
  • 90o
  • 60o
  • 30o
The plane 2x+3y+kz7=0 is parallel to the line whose direction ratios are (2,3,1), then k=
  • 5
  • 8
  • 1
  • 0
If the foot of the perpendicular from (0,0,0) to the plane is (1,2,2), then the equation of the plane is
  • x+2y+8z9=0
  • x+2y+2z9=0
  • x+y+z5=0
  • x+2y3z+1=0
The sum of the squares of sine of the angles made by the line AB with OX,OY,OZ where O is the origin is
  • 1
  • 2
  • 1
  • 3
The direction ratios of a normal to the plane passing through (0,1,1),(1,1,2) and (1,2,2) are
  • (1,1,1)
  • (2,1,1)
  • (1,2,1)
  • (1,2,1)
0:0:2


Answered Not Answered Not Visited Correct : 0 Incorrect : 0

Practice Class 12 Commerce Maths Quiz Questions and Answers