问题补充:
已知特称命题P:$x∈R,2x+1≤0,则命题P的否定是A.$x∈R,2x+1>0B.x∈R,2x+1>0C.$x∈R,2x+1≥0D.x∈R,2x+1≥0
答案:
B解析解:因为特称命题P:$x∈R,2x+1≤0,则命题P的否定是"x∈R,2x+1>0特称命题的否定就是全称命题,注意存在改为任意,结论变为否定即可。
已知特称命题P:$x∈R 2x+1≤0 则命题P的否定是A.$x∈R 2x+1>0B.x∈R 2x+1>0C.$x∈R 2x+1≥0D.x∈R 2x+1≥0
时间:2023-08-24 20:32:00
已知特称命题P:$x∈R,2x+1≤0,则命题P的否定是A.$x∈R,2x+1>0B.x∈R,2x+1>0C.$x∈R,2x+1≥0D.x∈R,2x+1≥0
B解析解:因为特称命题P:$x∈R,2x+1≤0,则命题P的否定是"x∈R,2x+1>0特称命题的否定就是全称命题,注意存在改为任意,结论变为否定即可。
已知特称命题P:$x∈R 2x+1≤0 则命题P的否定是A.$x∈R 2x+1>0B.x∈R 2x+1>0C.$x∈R 2x+1≥0D.x∈R 2x+1≥0
单选题已知命题P:?x∈R x2+2>2x.则它的否定是A.¬p:?x∈R x2+2<
2023-01-13