已知抛物线y=2x2-4x+m的顶点在x轴上,则m的值是______.
∵抛物线y=2x2-4x+m的顶点在x轴上,
∴b2-4ac=0,即16-8m=0,解得m=2.
____ is mentioned above, the number of the cattle here has been limited to 200.
A.It
B.Which
C.That
D.As
关于巨幼细胞贫血的非血液学表现,叙述正确的有()
A.一般无缺铁表现
B.口炎、舌炎、“镜面舌”、“牛肉舌”
C.末梢神经炎、共济失调
D.精神失常
E.锥体束征阳性、视力下降