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帮个忙帮个忙! 帮个忙帮个忙 帮个忙帮个忙明天要交的 兔子是不是最可爱的动物呢?帮个忙!帮个忙帮个忙! 集合A=｛-3,4｝,B=｛x|x²-2ax+b=0｝ B≠空集,若A∩B=B 求实数a,b的值速求啊~~~~帮个忙帮个忙. 帮个忙帮个忙,我在写作业,完形填空 Once I made a foolish mistake in the class ,a mistake ____1____ later proved very ____2____ in my English study noplaces ____3____ I should pay particular attention .That day ____4____ we were having a