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单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,双曲线的,简单几何性质,(3),-,直线与双曲线的位置关系,一、直线与椭圆的位置关系,：,（,2,）弦长问题,（,3,）弦中点问题,（,4,）经过焦点的弦的问题,（,1,）直线与椭圆位置关系,二、直线与双曲线位置关系种类：,X,Y,O,种类,:,相离,;,相切,;,相交,(,两个交点,一个交点,),两个交点 一个交点,0,个交点,相交,相,切,相,交,相离,交点个数,方程组解的个数,有没有问题,?,结论一：,1 0,个交点和两个交点的情况都正常,那么,依然可以用判别式判断位置关系,2,一个交点却包括了两种位置关系,:,相切和相交,(,特殊的相交,),那么是否意味着判别式等于零时,即可能相切也可能相交,?,判断下列直线与双曲线之间的位置关系：,1,2,相 切,相 交,试一下,:,判别式情况如何,?,一般情况的研究,显然,这条直线与双曲线的渐进线是平行的,也就是相交,.,把直线方程代入双曲线方程,看看判别式如何,?,根本就没有判别式,!,当直线与双曲线的渐进线平行时,把直线方程代入双曲线方程,得到的是一次方程,根本得不到一元二次方程,当然也就没有所谓的判别式了。,结论：判别式依然可以判断直线与双曲线的位置关系！,结论二：,判断直线与双曲线位置关系的操作程序,把直线方程代入双曲线方程,得到一元一次方程,得到一元二次方程,直线与双曲线的,渐进线平行,相交（一个交点）,计 算 判 别 式,0,=0,0,相交,相切,相离,例,1,、判断下列直线与双曲线的位置关系：,相交,(,一个交点,),相离,例,2,、设双曲线,与直线,相交于不同的点,A,、,B,，,求双曲线,C,的离心率,e,的取值范围,.,y,.,.,F,2,F,1,O,.,x,y,.,.,F,2,F,1,O,.,y,.,.,F,2,F,1,O,y,.,.,F,2,F,1,O,.,x,y,.,.,F,2,F,1,O,.,x,Thank you!,Bye Bye!,Module 2 Me,my parents and my friends,Unit 1 I can speak English,Introduce yourself:,My name is.,Im a.,Im from.,Im years old.,My favourite sport is.,Sports,play basketball,play football,play tennis,play tennis,table,play the piano,ride a bike,ride a horse,sing,swim,Match,Check the answer,Look,read and do,Swim,Sing,Ride a horse,Ride a bike,Play tennis,Play table tennis,Play football,Play basketball,What can Lingling do?,She can,swim,play football,and play tennis.,Listen and read,What,can,Betty do?,She,can,play football,play basketball,and speak English.,What,cant,Betty do?,She,cant,speak Chinese.,He,can,play football,play table tennis,ride a bike and speak English.,What,cant,Tony do?,What,can,Tony do?,He,cant,swim.,He,cant,speak Chinese.,Listen and repeat,Betty,can,play the piano.,Tony,can,play table tennis.,My friend,cant,speak English.,Betty,cant,play basketball.,Make a dialogue,Example:,-A:,Can,Betty speak English?,-B:Yes,she,can.,-A:,Can,Tony swim?,-B:No,he,cant.,Name:,Can,Cant,Play basketball,Play football,Play table tennis,Play tennis,Play the piano,Ride a bike,Ride a horse,Sing,Swim,Cook,-Can you cook?,-Yes,I,can.,/,No,I,cant,.,Summery,I can.I cant.,He/She can.He/she cant.,Some sports,Can you?Yes,I can.,No,I cant.,Can he/she?Yes,he/she can.,No,he/she cant.,Workbook,
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