题目

--Have you ever been to South Tower Park?---Yes. I ___________there a few months ago.A. went B. have been C. have gone 答案：【答案】A【解析】句意：——你曾经去过南塔公园吗？——是的，几个月前我去那儿了。have been to曾经去过某地； have gone to去某地了；根据a few months ago.可知用过去时态；故选A已知关于x的方程x2+（4k+1）x+2k-1=0．（1）求证：不论k取何值此方程总有两个不相等的实数根．（2）当k取绝对值最小的实数时，求此时方程的根．