定积分
(n为正整数)=______。
参考答案:[*]
解析:[考点] 计算周期函数定积分 [答案解析] [*]是以[*]为周期的连续周期函数,而且是偶函数,则 [*]
下列描述中正确的是 ( )
A.CS2分子的立体构型为V形
B.的空间构型为平面三角形
C.SF6中有每个原子均满足最外层8电子稳定结构
D.SiF4和的中心原子均为sp3杂化
At the meeting, the people were ____by the kindness and natural beauty of his mother in spite that there
is a scar in her face. [ ]
A. impressed
B. surprised
C. excited
D. comforted