选修4-5:不等式选讲
已知函数f(x)=|2x+1|,g(x)=|x|+a-1
(1)当a=1,解不等式f(x)≥g(x);
(2)若存在x∈R,使得f(x)≤g(x)成立,求实数a的取值范围.
考点分析:
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