已知y=6x2-ax-a2,且当x=1时,y=0,求a的值.
把x=1,y=0代入y=6x2-ax-a2,
得到一个关于a的方程:6-a-a2=0,
解得a=2或-3.
—What a nice meal! Thank you for having us.
— _________. I’m so glad you enjoyed it.[ ]
A. It's nothing
B. It is a pleasure
C. Not nice enough
D. With pleasure
患儿男,生后2天,出生体重为2400g。因吸入性肺炎入院,入院时患儿呼吸急促,口唇稍发绀。即置于辐射保暖床上抢救。
该患儿吸氧的流量应选择每分钟为()
A.1L
B.2L
C.3L
D.4L
E.5L