This task is for a school assignment where I have solved a differentialeq. with Eulers formula in a self made proc where i get the position in x and y as x[i] and y[i] where 'i' is steplength. When i use the solve(x[i]=0,i) I'm not getting any result because i is an integer with no decimals. So i=4 might return 1 and i=5 might return -1, but I'm not getting any answer i=4,5...