问题
选择题
一元二次方程-3x2+3x+4=0,变二次项系数为正,且根不变的是( )
A.3x2+3x+4=0
B.3x2-3x+4=0
C.3x2+3x-4=0
D.3x2-3x-4=0
答案
方程的两边同时除以-1,得:
3x2-3x-4=0.
故选D.
一元二次方程-3x2+3x+4=0,变二次项系数为正,且根不变的是( )
A.3x2+3x+4=0
B.3x2-3x+4=0
C.3x2+3x-4=0
D.3x2-3x-4=0
方程的两边同时除以-1,得:
3x2-3x-4=0.
故选D.
选择下列方框中的词语或短语完成下面对话。(共5小题,每小题1分)
B: To be a great 小题1:__________ like my uncle. A: Really? But don't you think it is more 小题2:__________ than any other job? B: Maybe. However, I 小题3:__________ to get a kind of exciting life. A: I see. By the way, do you know some things about your uncle? B: Yes, he caught bad men in a 小题4: __________ case again. A: How great he is! I hope your dream will 小题5:_________ true, too. B: Thanks a lot. |