if e2= (1,1,1) and e2=(1,1,-1) a and b are two vectors such that e1=2a+b and e2=a+2b then the angle between a and b is - cos-1(7/9)
- cos-1(7/11)
- cos-1(-7/11)
- cos-1[6∫2/11]
if e2= (1,1,1) and e2=(1,1,-1) a and b are two vectors such that e1=2a+b and e2=a+2b then the angle between a and b is
- cos-1(7/9)
- cos-1(7/11)
- cos-1(-7/11)
- cos-1[6∫2/11]