问题
选择题
命题“∃x0∈R,使得x2-x>0”的否定是( )
A.∀x∈R,x2-x>0
B.∀x∈R,x2-x≤0
C.∃x0∉R,使得x2-x<0
D.∃x0∉R,使得x2-x≤0
答案
∵命题“∃x0∈R,使得x2-x>0”是特称命题.
∴否定命题为:∀x∈R,x2-x≤0.
故选B.
命题“∃x0∈R,使得x2-x>0”的否定是( )
A.∀x∈R,x2-x>0
B.∀x∈R,x2-x≤0
C.∃x0∉R,使得x2-x<0
D.∃x0∉R,使得x2-x≤0
∵命题“∃x0∈R,使得x2-x>0”是特称命题.
∴否定命题为:∀x∈R,x2-x≤0.
故选B.