This is a poisson mass function for the future lifetime of a newborn: (k) = λk e- λ/k! for all k>= 0,
where k is a discrete random variable.
Find an expression for (k)
(find an expression for S naught of k)

Find the directions in which the function increases and decreases most rapidly at upper p 0p0. then find the derivatives of the function in these directions. f(x,y)equals=x squared plus xy plus y squaredx2+xy+y2, upper p 0p0left parenthesis 1 comma negative 4 right parenthesis