If a + b + c = 0 and |a| = 1, |b| = 1, |c| =` sqrt3` ,then the angle between a and b is

If a + b + c = 0 and |a| = 3, |b| = 4 and |c| = sqrt(37) the angle between a and b is

If |a|=1,|b|=3 and |a-b|=sqrt(7) , then the angle between a and b is

If a+b+c=0 and |a|=sqrt(37),|b|=3, |c|=4 then the angle between b and c is

If vec a + vec b + vec c = 0 and |vec a|= 3, |vec b| = 4 and |vec c| = sqrt37 , then the angle between vec a and vec b is

If three vectors a,b,c are such that a !=0 and a xx b = 2 (a xx c), |a| = |c| = 1, |b| = 4 and the angle between b and c is cos^(-1) (1/4), then b - 2c = lambda a where lambda =

Vectors a and b are such that |a|=1,|b|=4 and a.b=2." If " c=2axxb-3b , then the angle between b and c is

If the arithmetic mean of 0, 5, 4, 3 is a , that of -1, 0, 1, 5, 4, 3 is b and that of 5, 4, 3 is c , then the relation between a , b and c is a=b=c (b) a : b : c=3:2:4 (c) 4a=5b=c (d) a+b+c=12