double a = 1.0;double b = 3.0;double c = -4.0;double r1 = (-b + Math.sqrt((b*b-(4*a*c))))/(2*a);double r2 = (-b - Math.sqrt((b*b-(4*a*c))))/(2*a);System.out.println(r1);System.out.println(r2);System.out.println(r1 == 1 && r2 == -4 ? "测试通过" : "测试失败");