Volume of parallelepiped determined by vectors a,b and c is 2. Then the volume of the parallelepiped determined by vectors 2(a×b),3(b×c) and 2(c×a) is
(Q)
Volume of parallelepiped determined by vectors a,b and c is 5. Then the volume of the parallelepiped determined by vectors 3(a+b),3(b+c) and 2(c+a) is
(R)
Area of a triangle with adjacent sides determined by vectors a and b is 20. Then the area of the triangle with adjacent sides determined by vectors (2a+3b) and (a−b) is
(S)
Area of a parallelogram with adjacent sides determined by vectors a and b is 30. Then the area of the parallelogram with adjacent sides determined by vectors (a+b) and a is
List-II
(1)
100
(2)
30
(3)
24
(4)
60
Answer:P → 3, Q → 4, R → 1, S → 2
Let a,b,c be three non-coplanar vectors and p,q,r are vectors defined by the relations p=[abc]b×c,q=[abc]c×a,r=[abc]a×b then the value of the expression (a+b)⋅p+(b+c)⋅q+(c+a)⋅r is equal to
(A)
0
(B)
1
(C)
2
(D)
3
Answer:D
Let V be the volume of the parallelopiped formed by the vectors a=a1i^+a2j^+a3k^, b=b1i^+b2j^+b3k^, c=c1i^+c2j^+c3k^. If ar,br,cr, where r=1,2,3, are non-negative real numbers and ∑r=13(ar+br+cr)=3L, show that V≤L3.
The volume of the parallelopiped whose sides are given by OA=2i^−2j^,OB=i^+j^−k^,OC=3i^−k^, is
(A)
4/13
(B)
4
(C)
2/7
(D)
none of these
Answer:D
Match the statements / expressions given in Column-I with the values given in Column-II.
List-I
(P)
Root(s) of the equation 2sin2θ+sin22θ=2
(Q)
Points of discontinuity of the function f(x)=[π6x]cos[π3x], where [y] denotes the largest integer less than or equal to y
(R)
Volume of the parallelopiped with its edges represented by the vectors i^+j^,i^+2j^ and i^+j^+πk^
(S)
Angle between vector a and b where a,b and c are unit vectors satisfying a+b+3c=0
List-II
(1)
π/6
(2)
π/4
(3)
π/3
(4)
π/2
(5)
π
Answer:Q → 4, Q → NaN, R → 5, S → 3
If a=101(3i^+k^) and b=71(2i^+3j^−6k^), then the value of (2a−b)⋅[(a×b)×(a+2b)] is
(A)
−3
(B)
5
(C)
3
(D)
−5
Answer:D
If A,B,C,D are any four points in space, prove that ∣AB×CD+BC×AD+CA×BD∣=4(area of triangle ABC).
Let ΔPQR be a triangle. Let a=QR,b=RP and c=PQ. If ∣a∣=12,∣b∣=43,b⋅c=24, then which of the following is (are) true?
* Multiple Correct Options
(A)
2∣c∣2−∣a∣=12
(B)
2∣c∣2+∣a∣=30
(C)
∣a×b+c×a∣=483
(D)
a⋅b=−72
Answer:A, C, D
If a,b,c are three non-zero, non-coplanar vectors and b1=b−∣a∣2b⋅aa, b2=b+∣a∣2b⋅aa, c1=c−∣a∣2c⋅aa−∣b1∣2c⋅b1b1, c2=c−∣a∣2c⋅aa−∣b∣2c⋅bb, c3=c−∣a∣2c⋅aa−∣b2∣2c⋅b2b2, c4=c−∣a∣2c⋅aa, then the set of orthogonal vectors is
(A)
(a,b1,c3)
(B)
(a,b1,c2)
(C)
(a,b1,c1)
(D)
(a,b2,c2)
Answer:B
If (a×b)×c=a×(b×c) where a,b and c are any three vectors such that a⋅b=0,b⋅c=0 then a and c are
(A)
inclined at an angle of π/3 between them
(B)
inclined at an angle of π/6 between them
(C)
perpendicular
(D)
parallel
Answer:D
The edges of a parallelopiped are of unit length and are parallel to non-coplanar unit vectors a^,b^,c^ such that a^⋅b^=b^⋅c^=c^⋅a^=21. Then, the volume of the parallelopiped is