【考查知识点：极值】 函数的极大值点是（   ）

<em><span style、"font-family: 'times new roman', times, serif;">x</span></em>=1

<em><span style、"font-family: 'times new roman', times, serif;">x</span></em>=-1

<em><span style、"font-family: 'times new roman', times, serif;">x</span></em>=3

<span style、"font-family: 'times new roman', times, serif;"><em>x</em></span><span>=0</span>