问题
选择题
已知命题p:∃x∈R,x2-3x+2=0,则¬p为( )
A.∃x∉R,x2-3x+2=0
B.∃x∈R,x2-3x+2≠0
C.∀x∈R,x2-3x+2=0
D.∀x∈R,x2-3x+2≠0
答案
∵命题p:“∃x∈R,x2-3x+2=0”是特称命题
∴¬p:∀x∈R,x2-3x+2≠0
故选D.
已知命题p:∃x∈R,x2-3x+2=0,则¬p为( )
A.∃x∉R,x2-3x+2=0
B.∃x∈R,x2-3x+2≠0
C.∀x∈R,x2-3x+2=0
D.∀x∈R,x2-3x+2≠0
∵命题p:“∃x∈R,x2-3x+2=0”是特称命题
∴¬p:∀x∈R,x2-3x+2≠0
故选D.