1、几何画板动画演示几何画板动画演示解法一解法一:()(1)(2).xfxxea(1)0fe (2)0falim(2)0,xxxe解法一解法一:()(1)(2).xfxxea(1)0fe (2)0fa2()(2)(1)bf bbea b2(2)(1)2aba b23()0.2a bb解法一解法一:()(1)(2).xfxxea()01ln(2).fxxxa或0ln(2)1,2eaa若,则解法一解法一:()(1)(2).xfxxea()01ln(2).fxxxa或02ea若,2ea 若,(0,)解法二解法二:(分离参数分离参数)2(2)()(1)xx eg xx(0,)(0,)1212xx极值点极值
2、点极值点居中极值点居中极值点偏移极值点偏移1202xxx1202xxx极值点偏移问题的极值点偏移问题的求解策略求解策略(0,)1212122xxxx 122xx122xx12()(2)f xfx220()(2)f xfx2(2)0fx22(1,).x则222222(2)(1),xfxx ea x 由于22222()()012).(xxafxxe而222222(2)(2).xxfxx exe 所以2()(2).xxg xxexe 令2()(1)().xxg xxee令122.xx故12()(2)f xfx只需证122xx要证122xx 只需证22()(2)f xfx只需证12()()f xf x原始型差函数()()(2)F xf xfx()(1)(1)F xfxfx构造构造不妨设121,xx 12,2,1xx 对称型差函数