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参考答案:对
对于一元二次方程ax2+bx+c=0(a≠0):
(1)当b2-4ac______0⇔方程有两个不相等的实数根.
(2)当b2-4ac______0⇔方程有两个相等的实数根.
(3)当b2-4ac______0⇔方程无实数根.
I don't like the way ________ you laugh at her.[ ]
A. which
B. in which
C. by which
D. on which