If `|veca+vecb|lt|vecavecb|` then the angle between `veca and vecb` lies in the interval (A) `(-pi/2, pi/2)` (B) `(0,pi0)` (C) `(pi/2,(3pi)/2)` (D) (0,2pi)`

If |vec a+vec b|<|vec a-vec b|, then the angle between vec a and vec b can lie in the interval a.(pi/2,pi/2) b.(0,pi) c.(pi/2,3 pi/2) d.(0,2 pi)

If |veca.vecb|=sqrt(3)|vecaxxvecb| then the angle between veca and vecb is (A) pi/6 (B) pi/4 (C) pi/3 (D) pi/2

If veca+vecb+vecc=0, |veca|=3, |vecb|=5, |vecc|=7, then angle between veca and vecb is (A) pi/6 (B) (2pi)/3 (C) (5pi)/3 (D) pi/3

If |veca|=4,|vecb|=2 and angle between veca and vecb is pi/6 then (vecaxxvecb)^2 is (A) 48 (B) (veca)^2 (C) 16 (D) 32

f(x) = cos x is strictly increasing in the interval : (a) ((pi)/(2),pi) (b) (pi,(3 pi)/(2)) (c) (0,(pi)/(2))

If the unit vectors veca and vecb are inclined at an angle 2theta such that |veca-vecb|lt1 and 0lethetalepi then theta lies in the intervasl. (A) [0,pi/6] (B) (5pi/6,pi] (C) [pi/2,5pi/6] (D) [pi/6,pi/2]

If |vecc|=2 , |veca|=|vecb|=1 and vecaxx(vecaxxvecc)+vecb=vec0 then the acute angle between veca and vecc is (A) pi/6 (B) pi/4 (C) pi/3 (D) (2pi)/3

If the angle between veca and vecb is (pi)/(3) , then angle between 2veca and -3vecb is :

The eqution sin x+x cos=0 has at least one root in (A)(-(pi)/(2),0)(B)(0,pi)(C)(pi,(3 pi)/(2)) (D) (0,(pi)/(2))

Let veca,vecb and vecc be three unit vectors such that vecaxx(vecbxxvecc)=sqrt(3)/2(vecb+vecc) . If vecb is not parallel to vecc then the angle between veca and vecb is (A) (5pi)/6 (B) (3pi)/4 (C) pi/2 (D) (2pi)/3