浙大数学优辅高考数学拉档提分全攻略导数闻杰编著9787308215985 导数概组合函数对数均值不等式函数放缩不等恒成高考命题热点

海外直订Inequalities between First Four Moments and Standard Power Means 前四阶矩与标准幂均值的不等式