# I: The vectors 6i+2j+k, 2i-9j+6k are mutually perpendicular II: The vectors i+2j-k, 2i+j+k are mutually perpendicular

1.  Only I is true

2.  Only II is true

3.  both I and II are true

4.  neither I nor II are true

4

Only I is true

Explanation :
No Explanation available for this question

# I: If the vectors a=(1, x, -2), b=(x, 3, -4) are mutually perpendicular,then x=2 II: If a=i+2j+3k, b=-i+2j+k, c=3i+j and a+tb is perpendicular to

1.  Only I is true

2.  Only II is true

3.  both I and II are true

4.  neither I nor II are true

4

Only II is true

Explanation :
No Explanation available for this question

# I: If |a+b|=|a-b| then (a, b)= π/2 II: If a, b, a+b are unit vector then (a, b)=2π/3

1.  Only I is true

2.  Only II is true

3.  both I and II are true

4.  neither I nor II are true

4

both I and II are true

Explanation :
No Explanation available for this question

# I: If |a.b|=|axb| then (a, b)=π/4 II: If |a.b|=|axb| then (a, b)=3π/4

1.  Only I is true

2.  Only II is true

3.  both I and II are true

4.  neither I nor II are true

4

both I and II are true

Explanation :
No Explanation available for this question

# I: If |a+b|=|a-b| then |axb|=0 II: (axb)2+(a.b)2=|a|2|b|2

1.  Only I is true

2.  Only II is true

3.  both I and II are true

4.  neither I nor II are true

4

Only II is true

Explanation :
No Explanation available for this question

# I: If (a+b).c=(a-b).c=0 then (axb)xc=0 II: If ax(bxc) is a vector perpendicular to a, b, c

1.  Only I is true

2.  Only II is true

3.  both I and II are true

4.  neither I nor II are true

4

Only I is true

Explanation :
No Explanation available for this question

# I: For any vector a, (axi)2+(axj)2+(axk)2=2a2 and (a.i)2+(a.j)2+(a.k)2=a2

1.  Only I is true

2.  Only II is true

3.  both I and II are true

4.  neither I nor II are true

4

Only I is true

Explanation :
No Explanation available for this question

# I: If a=i+j-k, b=2i-3j+2k, c=13i-7j+3k then [a b c]=0 II: If a, b, c are mutually perpendicular unit vectors, tehn [a b c]2=1

1.  Only I is true

2.  Only II is true

3.  both I and II are true

4.  neither I nor II are true

4

both I and II are true

Explanation :
No Explanation available for this question

# I: The volume of the parallelepiped with edges 2i-4j+5k, i-j+k, 3i-5j+2k is 8 II: The volume of the tetrahedron  with edges i+2j+2k,2i-j+2k,

1.  Only I is true

2.  Only II is true

3.  both I and II are true

4.  neither I nor II are true

4

both I and II are true

Explanation :
No Explanation available for this question

# I: If the vectors 2i-3j+4k, i+2j-k, xi-j+2k are coplanar then x=8/5 II: If  the volume of the parallelopiped with edges 2i+3j, i+j+k, xi+4j+2

1.  Only I is true

2.  Only II is true

3.  both I and II are true

4.  neither I nor II are true

4