46．设函数f(x)=ax2ex−blnxf(x)=ax^{2}e^{x}-blnxf(x)=ax2ex−blnx的图象在点(1,e)(1,e)(1,e)处切线的斜率为3e−1(e≈2.72)3e-1(e\approx 2.72)3e−1(e≈2.72)．（1）求实数aaa，bbb的值．（2）证明：f(x)>52x3f(x)>\frac{5}{2}x^{3}f(x)>25x3．