IIT JEE , AIEEE Forum - Mathematics , Vectors

studyid

hey jv604,
see i have a sol. to yr 3rd q.
it is as follows :

see vector a =BC vctor, then vector b = AC vector and lastly vctor c=AB vctor.

now since these three vectors a,b n c for a

, it is very obvious acc, to

law of vector addition, that a+b+c=0.

Now thats a imp. relation.

now take cross product of a on both the sides,

a x (a+ b + c) = a x 0
a x b + a x c =0
axb=cxa.----(1)

now take cross product on both sides with b

b x (a+b+c)=b x 0
bxa+bxc=0
bxc=axb---(2)

hnce by 1 & 2,
axb=bxc=cxa

Ask & Discuss Questions with Community & Experts