Minimum

package fadsgedfsg;

public class Program {

    public static void main(String[] args) {
        double x,y,z=y=x=20,
        epsmax=0.001,
        alpha=0.1;
        int itermax=100;
        for(int iter=1;iter<itermax;++iter){
            double u=(x-2)*(x-2)+(y-5)*(y-5)+(z+4)*(z+4);
            double dfdx=2*(x-2);
            double dfdy=2*(y-5);
            double dfdz=2*(z+4);

            double xn=x-alpha*dfdx;
            double yn=y-alpha*dfdy;
            double zn=z-alpha*dfdz;

            double eps=(xn-x)*(xn-x)+(yn-y)*(yn-y)+(zn-z)*(zn-z);
            if(eps<epsmax)break;
            x=xn;
            y=yn;
            z=zn;
            System.out.println(iter+" "+xn+" "+yn+" "+zn+" "+u);
        }
        System.out.println("Koniec");
    }

}