Find the projection of the vector `hat(i)-hat(j)` on the vector `hat(i)+hat(j)`.

Explanation

Let `a = hat(i)-hat(j),b=hat(i)+hat(j)`
Projection of `vec(a)` on `vec(b)` is given by , `(vec(a).vec(b))/|b|=((hat(i)-hat(j)).(hat(i)+hat(j)))/(sqrt(1^2+1^2))=(1xx1+(-1)xx1)/(sqrt(2))=0`
Hence, the projection of vector `vec(a) ` on `vec(b)` is 0.