Thanks Robert, That helped. The only problem i have left is that I have to optimize an objective function that contains matrices, is that possible? how? Can I make Maple export the results into a matrix? how? If you could help me I would be very grateful, Arnold

Thank you very much Mister Tarr!!! I have expanded the minimization problem and now it looks like this: b(1,t)*a(1,t)+b(2,t)*a(2,t)+b(3,t)*a(3,t) with constraint: 1.016*a(1)+1.016*a(2)+1.04*a(3)=1 I have the input for b from t=1 to t=5 and that is as far as it goes. Now I need to minimize this problem for these inputs, how do I do that with maple??? Use a matrix? What would be the commands? Thanks in advance, Arnold