已知集合A={x|ax2+2x+1=0}. (1)若A中只有一个元素,求a的值; 发布时间:2017-03-31 14:12 │ 来源:www.tikuol.com 题型:解答题 问题: 已知集合A={x|ax2+2x+1=0}.(1)若A中只有一个元素,求a的值;(2)若A中至多只有一个元素,求a的取值范围.
题型:解答题 Britain occupied Java during the Napoleonic Wars. Both the British and later the Dutch tried to centralize and reform Java’s administration. The Dutch wavered between opening the area to individual enterprise and reverting to a monopoly system.A.resolvedB.reckonedC.hesitatedD.discriminated 查看答案