关于x的方程x2-mx-2=0的两根互为相反数,那么m值为______.
设方程的根为x1,x2.
则x1+x2=-(-m),
由题意知x1+x2=0,
所以m=0.
故应填:0.
X线平片示两肺野出现大小、密度、分布三均匀的弥漫性粟粒结节,直径约1~2mm,边界清楚,应考虑为()
A.亚急性血行播散型肺结核
B.病毒性肺炎
C.支气管肺泡癌
D.小叶性肺炎
E.急性血行播散型肺结核
根据首字母及汉语提示,完成下列单词的拼写,使句意明确,语言通畅。
小题1:My friends will f_____ (飞) to London to watch the ceremony of the 2012 London
Olympic Games.
小题2:You have to be p______(耐心) if you’re waiting at the end of a long queue.
小题3:Sandy has lots of sports c______(收藏).
小题4:Do you think this kind of water is s______ (安全)for drinking.
小题5:Students at school shouldn’t get their ears p___.(刺穿)