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

If veca,vecb,vecc are three vectors such that veca+2vecb+vecc=vec0 and |veca|=3,|vecb|=4,|vecc|=7 , find the angle between veca and vecb .

If veca,vecb,vecc are three vectors such that veca+2vecb+vecc=vec0and|veca|=3,|vecb|=4,|vecc|=7 , find the angle between vecaandvecb .

If veca,vecb,vecc are three vectors such that veca+2vecb+vecc=vec 0 and|veca|=3,|vecb|=4,|vecc|=7 find the angle between vecaandvecb

If veca ,vecb, vec c are three vectors such that veca + 2 vecb + vecc = vec0, and |veca|=3, |vecb|=4, |vec c|=7, find the angle between vec a and vecb.

If veca+vecb+vecc =0, |veca|=3, |vecb|=5, |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 .

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

veca and vecb are two vectors such that |veca|=1 ,|vecb|=4 and veca. Vecb =2 . If vecc = (2vecaxx vecb) - 3vecb then find angle between vecb and vecc .