Find the value of `lambda` so that the three vectors are co-planar. (2,-1,1), (1,2,-3) and (3,λ,5)

Explanation

Let `veca = (2,-1,1), vecb = (1,2,-3), vecc = (3,lambda,5)`
If `veca,vecb,vecc` are coplanar then `vecaxxvecb.vecc = 0`