Suppose that f := x -> k where k is a constant. Then sum(f(x), i = 1 .. n) is nk. Now suppose that I have a non-constant function of x defined as f := x -> exp(-x). Now I have y defined to be y := product(f(x__i), i = 1 .. n) and the answer I am getting is wrong which is exp(-x__i)^n. So it seems like Maple treats every expression or function under the summation to be constant. The correct answer is supposed to be exp(-sum(x__i, i = 1 .. n)). I am looking for assistance on how to fix this. Below is my MWE:

I am doing Ito calculus workings in Maple. With B__t as a standard Brownian motion, the following results are true:

I am solving a computer materials science problem in the MAPLE software package. Solving this problem requires calculating the eigenvalues ​​of matrices of sufficiently large sizes (16×16 or more) and further plotting of graphs using these eigenvalues. The elements of these matrices are trigonometric functions of fairly curved angles. I encountered the problem that when the matrix reaches 24×24 or more in size, MAPLE simply freezes and stops producing any results. I am confident in the correctness of my code, because when working with matrices whose dimensions are smaller than 24×24, MAPLE produces correct results. I calculate the eigenvalues ​​of matrices using the eigenvals() function.