若命题“x∈R,x^2+ax+1

题目

若命题“x∈R,x^2+ax+1<=0”是假命题,则实数a的取值范围是

答案

∵“x∈R,x^2+ax+1<=0”是假命题
∴“x∈R,x^2+ax+1≧0”是真命题
△≦0
△=a²－4≤0
a∈[-2,2]