[" 4.In a parallelogram "ABCD" ,if "vec AB=vec a" and "],[qquad [vec BC=vec b," show that "vec AC=vec a+vec b" and "],[bar(BD)=vec b-vec a]]

If ABCD is a parallelogram and vec AB = vec a , vec BC= vec b then show that vec AC = vec a+ vec b and vec BD = vec b- vec a .

In a parallelogram ABCD. Prove that vec(AC)+ vec (BD) = 2 vec(BC)

ABCD is a parallelogram . If vec(AB)=vec(a), vec(BC)=vec(b) , then what vec(BD) equal to ?

Given a parallelogram ABCD. If |vec AB|=a,|vec AD|=b&|vec AC|=c, then vec DB*vec AB has the value

A parallelogram ABCD. Prove that vec(AC)+ vec (BD) = 2 vec(BC) '

If vec c is normal to vec a and vec b , show that vec c is normal to vec a+ vec b and vec a - vec b .

Given a parallelogram ABCD . If |vec(AB)|=a, |vec(AD)| = b & |vec(AC)| = c , then vec(DB) . vec(AB) has the value

Given a parallelogram ABCD . If |vec(AB)|=a, |vec(AD)| = b & |vec(AC)| = c , then vec(DB) . vec(AB) has the value

For any three vectors vec a,vec b and vec c , show that vec a- vec b,vec b- vec c and vec c- vec a are coplanar.

If ABCD is a parallelogram and vec AB = vec a , vec BC= vec b then give geometrical significance of |quad vec a+ vec b|=|quad vec a- vec b| .