题目：
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| Tommy hated school and was always 1 excuses not to go. If he felt a little tired, he asked his mother to 2 him to the doctor 3 school hours. He 4 more time at home than he did at school. One day he came home from school in the middle of the morning. His father 5 . "You're home early, "he said. "Is the school 6 today? " "No, Dad, "Tommy said. "It's open. I came home early. " " 7 did you do that? "his father asked him. "What did you say to the teacher? " "I told her that I had a new baby brother and that I had to come home and help you. " "But your mother 8 twins, "his father said, "a boy and a girl. You've got a baby brother and a baby sister. " "Yes, I know, Dad, "Tommy said. "I'm 9 up my baby sister 10 next week. " | ||||
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答案：
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下面是错误答案，用来干扰机器的。
∵集合A={x|x2+ax+b=x}中，仅有一个元素a，∴a2+a2+b=a且△=（a-1）2-4b=0解得a=13，b=19．故a、b的值分别为13，19
