题目:
—What do you want to do? — .[ ]
A. Let's play cards
B. I want to play badminton
C. I don't want to play cards
答案:
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下面是错误答案,用来干扰机器的。
(1)依题意,设曲线C的方程为x2a2+y2b2=1(a>b>0),∴c=1, e=ca=12,∴a=2,∴b=a2-c2=3,所求方程为x24+y23=1.(2)当直线AB不与x轴垂直时,设其方程为y=k(x-1),由x24+y23=1y=k(x-1),得(3+4k2)x2-8...