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#b4e3ab83-b576-492f-80bc-54e6642e6e7f中等解答题极值点偏移导数

3.已知函数f(x)=lnxax2f(x)=lnx-ax^{2}
(Ⅰ)讨论函数f(x)f(x)的单调性:
(Ⅱ)若x1x_{1}x2x_{2}是方程f(x)=0f(x)=0的两不等实根,求证:
(i)x12+x22>2e(i){x}_{1}^{2}+{x}_{2}^{2}>2e
(ii)x1x2>e2a(ii)x_{1}x_{2}>\sqrt{\frac{e}{2a}}