P
pham_khanh


cho 2 vec to: a (x;y;z)
b(x';y';z')
cm tich co huong cua 2 vec to a va b la 1 vec to co toa do
(yz'-y'z ; zx'-z'x ; xy'-x'y)
cac bac co gang giup em voi





b(x';y';z')
cm tich co huong cua 2 vec to a va b la 1 vec to co toa do
(yz'-y'z ; zx'-z'x ; xy'-x'y)
cac bac co gang giup em voi