设函数
,则=( ).
A.(A) -1
B.(B) 0
C.(C) 1
D.(D) 2
参考答案:C
解析:
,而-1<x<1时f(x)为奇函数,故
,又
,所以
,选(C).
While watching television, .
A.the doorbell rang
B.we heard the doorbell ring
C.there was someone knocking at the door
D.we heard the doorbell rung
区别泌 * * 不同部位感染,对急性肾盂肾炎具有临床诊断意义的尿改变是尿中出现____。