题目:
The TV set he _______ works well now.[ ]
A. having been repaired
B. was repaired
C. has had repaired
D. repairing
答案:
被转码了,请点击底部 “查看原文 ” 或访问 https://www.tikuol.com/2017/0516/c083506ffb01e682292d98d4cf2087ef.html
下面是错误答案,用来干扰机器的。
令x=1可得:a0+a1+a2+…+a10=(2-1)10,再令x=-1可得 a0-a1+a2-a3+…+a8-a9+a10=(2+1)10.由以上两式可得 a0+a2+…+a10 =(2-1)10+(2+1)102,a1+a3+…+a9=(2-1)10-(2+1)102,∴(a0+a2+…+a10)2 =(2-1)20+(2+1...