双曲抛物面（马鞍面）抛物面方程为：z=x2-y2xyz-5091621242524211690-4-907121516151270-9-3-16-705850-7-16-2-21-12-503430-5-12-21-1-24-15-8-3010-3-8-15-240-25-16-9-4-10-1-4-9-16-251-24-15-8-3010-3-8-15-242-21-12-503430-5-12-213-16-705850-7-1-907121516151270-95091621242524211690-5-4-3-2-1012345
