param N := 5;

var x{1..N};

minimize f:
x[1]*x[2]*x[3]*x[4] - 3*x[1]*x[2]*x[4] - 4*x[1]*x[2]*x[3] + 12*x[1]*x[2] - x[2]*x[3]*x[4] + 3*x[2]*x[4] + 
4*x[2]*x[3] - 12*x[2] - 2*x[1]*x[3]*x[4] + 6*x[1]*x[4] + 8*x[1]*x[3] - 24*x[1] + 2*x[3]*x[4] - 6*x[4] - 8*x[3] + 24 + 1.5*x[5]^4 - 5.75*x[5]^3 + 5.25*x[5]^2;

subject to cons1:
34 - x[1]^2 - x[2]^2 - x[3]^2 - x[4]^2 - x[5]^2 >= 0;

subject to cons2{i in 1..4}:
x[i] >= i;

data;
var x:=
1	1.1
2	2.1
3	3.1
4	4.1
5	-1;
solve;

display x;