Q.No.6. a) Use Laplace Expansion to find the determinant of, 15 7 9 2 56 12 b) Use the bordered Hessian to determine whether the stationary value of z is a maximum or minimum. 3y -xy, subjectto sty=6 c) Take a Cobb-Douglas production function, find its Elasticities w.r.t output and Elasticity of Substitution with the help of partial derivatives. (Marks/6)