二次函数y=2x2-6的图象的对称轴是______.
∵y=2x2-6的二次项系数a=2,一次项系数b=0,
∴对称轴x=-b2a=0,即x=0.也就是y轴.
故答案为:y轴.
The number of foreign students attending Chinese universities rising steadily since 1997. [ ]
A. is
B. has been
C. are
D. have been
以下程序段的输出结果是 【6】 。 int i=9; printf("%o\n",i);