问题
解答题
若命题p的逆命题是q，命题q的否命题是r，则p是r的（ ）
A．逆命题
B．逆否命题
C．否命题
D．以上判断都不对
答案
命题p：若x，则y，其逆命题q：若y，则x，
那么命题q的否命题r：若非y，则非x，
所以p是r的逆否命题．
故选B．
搜题请搜索小程序“爱下问搜题”
若命题p的逆命题是q，命题q的否命题是r，则p是r的（ ）
A．逆命题
B．逆否命题
C．否命题
D．以上判断都不对
命题p：若x，则y，其逆命题q：若y，则x，
那么命题q的否命题r：若非y，则非x，
所以p是r的逆否命题．
故选B．
| 完形填空。 | |||
| This is a 1 of Tom’s family.This man 2 Mr. Smith. 3 is Tom’s father. 4 woman is Mrs.Smih. 5 is Tom’s mother. Who 6 this boy and 7 girl? The boy is Tom,Mr.Smith’s 8 . The 9 is Kae, Mr. Smith’s daughter. Kate is 10 sister. Tom and Kate are brother and sister. | |||
| ( )1. A. book ( )2. A. am ( )3. A. She ( )4. A. A ( )5. A. She ( )6. A. am ( )7. A. a ( )8. A. father ( )9. A. girl ( )10. A. Tom | B. photo B. is B. Her B. An B. Her B. is B. an B. son B. girls B. Toms | C. map C. be C. He C. This C. He C. be C. those C. cousin C. boy C. Tom’s | D. pen D. are D. His D. These D. His D. are D. this D. uncle D. boys D. Toms’ |