`veca+vecb+vecc=vec0, |veca|=3, |vecb|=5,|vecc|=9`,find the angle between `veca` and `vecc`.

If veca +vecb +vecc=0, |veca|=3,|vecb|=5, |vecc|=7 , then find the angle between veca and vecb .

If veca +vecb +vecc=0, |veca|=3,|vecb|=5, |vecc|=7 , then find the angle between veca and vecb .

If veca +vecb +vecc =vec0, |veca| =3 , |vecb|=5 and |vecc| =7 , then the angle between veca and vecb is

If |veca|+|vecb|=|vecc|and veca+vecb=vecc then find the angle between veca and vecb .

If |veca|=|vecb|=|vecc|and veca+vecb=vecc then find the angle between veca and vecb .

Three vectors veca,vecb,vecc are such that veca xx vecb=4(veca xx vecc) and |veca|=|vecb|= and |vecc|=1/4 . If the angle between vecb and vecc is pi/3 then vecb is

If veca,vecb, vecc are three vectors such that veca + vecb +vecc =vec0, |veca| =1 |vecb| =2, | vecc| =3 , then veca.vecb + vecb .vecc +vecc + vecc.veca is equal to

If three unit vectors veca, vecb and vecc " satisfy" veca+vecb+vecc= vec0 . Then find the angle between veca and vecb .

If veca, vecb and vecc are three vectors such that 3veca+4vecb+6vecc=vec0, |veca|=3, |vecb|=3 and |vecc|=4 , then the value of -864((veca.vecb+vecb.vecc+vecc.veca)/(6)) is equal to