问题
填空题
若命题“∃x∈R,使x2+(a-1)x+1<0”是假命题,则实数a的取值范围为______.
答案
命题“∃x∈R,使x2+(a-1)x+1<0”的否定是:““∀x∈R,使x2+(a-1)x+1≥0”
即:△=(a-1)2-4≤0,
∴-1≤a≤3
故答案是-1≤a≤3
若命题“∃x∈R,使x2+(a-1)x+1<0”是假命题,则实数a的取值范围为______.
命题“∃x∈R,使x2+(a-1)x+1<0”的否定是:““∀x∈R,使x2+(a-1)x+1≥0”
即:△=(a-1)2-4≤0,
∴-1≤a≤3
故答案是-1≤a≤3