命题“存在x∈R,x2+2x+2≤0”的否定是______.
“存在x∈R,使x2+2x+2≤0”的否定是:
任意x∈R,x2+2x+2>0,
故答案为:任意x∈R,x2+2x+2>0
It was generally believed that the show was not as successful as expected, but ________,
I think it was a great success. [ ]
A. personally
B. directly
C. publicly
D. secretly
裂隙灯显微镜检查时最常用的照明方法为
A.弥散光照明法
B.直接焦点照明法
C.角巩膜缘分光照明法
D.后部反光照明法
E.镜面反光照明法