ÌâÄ¿ÄÚÈÝ
Èçͼ£¬ÔÚͬһֱ½Ç×ø±êϵÖУ¬Õý±ÈÀýº¯Êýy1=kxÓë·´±ÈÀýº¯Êýy2=
µÄͼÏó·Ö±ð
½»ÓÚµÚÒ»¡¢µÚÈýÏóÏ޵ĵãB£¬D£¬ÒÑÖªµãA£¨-a£¬0£©£¬C£¨a£¬0£©£®
£¨1£©Ö±½ÓÅжϲ¢Ìîд£ºËıßÐÎABCDµÄÐÎ×´Ò»¶¨ÊÇ
£¨2£©¢Ùµ±µãB×ø±êΪ£¨p£¬2£©Ê±£¬ËıßÐÎABCDÊǾØÐΣ¬ÊÔÇóp¡¢kºÍaµÄÖµ£»
¢ÚÖ±½Óд³ö²»µÈʽkx£¾
µÄ½â¼¯£»
£¨3£©ÊÔ̽¾¿£ºËıßÐÎABCDÄܲ»ÄÜÊÇÁâÐΣ¿ÈôÄÜ£¬Ö±½Óд³öBµãµÄ×ø±ê£»Èô²»ÄÜ£¬ËµÃ÷ÀíÓÉ£®
2
| ||
x |
![](http://thumb.1010pic.com/pic3/upload/images/201212/66/cd28732c.png)
£¨1£©Ö±½ÓÅжϲ¢Ìîд£ºËıßÐÎABCDµÄÐÎ×´Ò»¶¨ÊÇ
ƽÐÐËıßÐÎ
ƽÐÐËıßÐÎ
£»£¨2£©¢Ùµ±µãB×ø±êΪ£¨p£¬2£©Ê±£¬ËıßÐÎABCDÊǾØÐΣ¬ÊÔÇóp¡¢kºÍaµÄÖµ£»
¢ÚÖ±½Óд³ö²»µÈʽkx£¾
2
| ||
x |
£¨3£©ÊÔ̽¾¿£ºËıßÐÎABCDÄܲ»ÄÜÊÇÁâÐΣ¿ÈôÄÜ£¬Ö±½Óд³öBµãµÄ×ø±ê£»Èô²»ÄÜ£¬ËµÃ÷ÀíÓÉ£®
·ÖÎö£º£¨1£©ÓɵãA£¨-a£¬0£©£¬C£¨a£¬0£©µÃOA=OC£¬ÔÙ¸ù¾Ý·´±ÈÀýº¯ÊýͼÏó¹ØÓÚÔµãÖÐÐĶԳƣ¬µÃµ½OB=OD£¬¸ù¾ÝƽÐÐËıßÐεÄÅж¨¼´¿ÉµÃµ½ËıßÐÎABCDΪƽÐÐËıßÐΣ»
£¨2£©¢Ù¹ýBµã×÷BE¡ÍxÖáÓÚEµã£¬°ÑB£¨p£¬2£©´úÈëy2=
£¬¿ÉÇó³öp=
£¬ÔòBµã×ø±êΪ£¨
£¬2£©£¬ÔÙÀûÓù´¹É¶¨Àí¼ÆËãOB=
=
=
£¬ÔÙ¸ù¾Ý¾ØÐεÄÐÔÖʵÃ
OB=OC£¬µÃµ½a=
£¬È»ºó°ÑB£¨
£¬2£©´úÈëy1=kx¿ÉÇó³ökµÄÖµ£»
¢ÚÏȵõ½·´±ÈÀýº¯ÊýµÄÐÔÖʵõ½µãDµÄ×ø±êΪ£¨-
£¬-2£©£¬È»ºó¹Û²ìͼÏóµÃµ½µ±-
£¼x£¼0»òx£¾
ʱ£¬Õý±ÈÀýº¯Êýy1=kxµÄͼÏó¶¼ÔÚ·´±ÈÀýº¯Êýy2=
µÄͼÏóµÄÉÏ·½£»
£¨3£©ÓÉÓÚ±ÈÀýº¯ÊýͼÏóÓë×ø±êÖáû½»µã£¬¼´BµãÓëµãD²»¿ÉÄÜÔÚyÖáÉÏ£¬¶øµãA¡¢µãCÔÚxÖáÉÏ£¬ÔòBDÓëAC²»¿ÉÄÜ´¹Ö±£¬¸ù¾ÝÁâÐεÄÅж¨·½·¨µÃµ½ËıßÐÎABCD²»ÄÜÊÇÁâÐΣ®
£¨2£©¢Ù¹ýBµã×÷BE¡ÍxÖáÓÚEµã£¬°ÑB£¨p£¬2£©´úÈëy2=
2
| ||
x |
3 |
3 |
BE2+OE2 |
22+(
|
7 |
OB=OC£¬µÃµ½a=
7 |
3 |
¢ÚÏȵõ½·´±ÈÀýº¯ÊýµÄÐÔÖʵõ½µãDµÄ×ø±êΪ£¨-
3 |
3 |
3 |
2
| ||
x |
£¨3£©ÓÉÓÚ±ÈÀýº¯ÊýͼÏóÓë×ø±êÖáû½»µã£¬¼´BµãÓëµãD²»¿ÉÄÜÔÚyÖáÉÏ£¬¶øµãA¡¢µãCÔÚxÖáÉÏ£¬ÔòBDÓëAC²»¿ÉÄÜ´¹Ö±£¬¸ù¾ÝÁâÐεÄÅж¨·½·¨µÃµ½ËıßÐÎABCD²»ÄÜÊÇÁâÐΣ®
½â´ð£º½â£º£¨1£©ËıßÐÎABCDµÄÐÎ×´Ò»¶¨ÊÇƽÐÐËıßÐΣ»![](http://thumb.1010pic.com/pic3/upload/images/201212/84/8fdac884.png)
£¨2£©¢Ù¹ýBµã×÷BE¡ÍxÖáÓÚEµã£¬Èçͼ£¬
°ÑB£¨p£¬2£©´úÈëy2=
£¬
¡àp=
=
£¬
¡àBµã×ø±êΪ£¨
£¬2£©£¬
¡àOB=
=
=
£¬
¡ßËıßÐÎABCDÊǾØÐΣ¬
¡àOB=OC£¬
¡àa=
£¬
°ÑB£¨
£¬2£©´úÈëy1=kxµÃ2=k•
£¬
½âµÃk=
£¬
¢ÚµãDÓëµãB¹ØÓÚÔµã¶Ô³Æ£¬µãDµÄ×ø±êΪ£¨-
£¬-2£©£¬
µÈʽkx£¾
µÄ½â¼¯Îª-
£¼x£¼0»òx£¾
£»
£¨3£©ËıßÐÎABCD²»ÄÜÊÇÁâÐΣ®ÀíÓÉÈçÏ£º
ÒòΪ·´±ÈÀýº¯ÊýͼÏóÓë×ø±êÖáû½»µã£¬¼´BµãÓëµãD²»¿ÉÄÜÔÚyÖáÉÏ£¬
ËùÒÔBDÓëAC²»¿ÉÄÜ´¹Ö±£¬
ËùÒÔËıßÐÎABCD²»ÄÜÊÇÁâÐΣ®
![](http://thumb.1010pic.com/pic3/upload/images/201212/84/8fdac884.png)
£¨2£©¢Ù¹ýBµã×÷BE¡ÍxÖáÓÚEµã£¬Èçͼ£¬
°ÑB£¨p£¬2£©´úÈëy2=
2
| ||
x |
¡àp=
2
| ||
2 |
3 |
¡àBµã×ø±êΪ£¨
3 |
¡àOB=
BE2+OE2 |
22+(
|
7 |
¡ßËıßÐÎABCDÊǾØÐΣ¬
¡àOB=OC£¬
¡àa=
7 |
°ÑB£¨
3 |
3 |
½âµÃk=
2
| ||
3 |
¢ÚµãDÓëµãB¹ØÓÚÔµã¶Ô³Æ£¬µãDµÄ×ø±êΪ£¨-
3 |
µÈʽkx£¾
2
| ||
x |
3 |
3 |
£¨3£©ËıßÐÎABCD²»ÄÜÊÇÁâÐΣ®ÀíÓÉÈçÏ£º
ÒòΪ·´±ÈÀýº¯ÊýͼÏóÓë×ø±êÖáû½»µã£¬¼´BµãÓëµãD²»¿ÉÄÜÔÚyÖáÉÏ£¬
ËùÒÔBDÓëAC²»¿ÉÄÜ´¹Ö±£¬
ËùÒÔËıßÐÎABCD²»ÄÜÊÇÁâÐΣ®
µãÆÀ£º±¾Ì⿼²éÁË·´±ÈÀýº¯Êý×ÛºÏÌ⣺·´±ÈÀýº¯ÊýͼÏóΪ˫ÇúÏߣ¬¹ØÓÚÔµãÖÐÐĶԳƣ»µãÔÚͼÏóÉÏ£¬µãµÄ×ø±êÂú×ãÆä½âÎöʽ£»ÕÆÎÕƽÐÐËıßÐΡ¢ÁâÐεÄÅж¨ÓëÐÔÖʺ͹´¹É¶¨Àí£®
![](http://thumb2018.1010pic.com/images/loading.gif)
Á·Ï°²áϵÁдð°¸
Ïà¹ØÌâÄ¿