·ÖÎö £¨1£©¸ù¾Ýµ±x=-1ºÍx=3ʱ£¬¶þ´Îº¯ÊýµÄÖµyÏàµÈ£¬Çó³ö¶Ô³ÆÖᣬÓɵãAµÄ×ø±êΪ£¨-2£¬0£©£¬µÃµ½Bµã×ø±êΪ£¨4£¬0£©£¬½«A£¨-2£¬0£©£¬B£¨4£¬0£©·Ö±ð´úÈë½âÎöʽy=ax2+bx-4¼´¿É£»
£¨2£©Èçͼ1£¬×÷EF¡ÍxÖáÓÚF£¬Çó³öAD½âÎöʽ£¬¿ÉµÃµ½PE½âÎöʽΪy=-x+g£¬ÉèE£¨t£¬2t-8£©£¬½«E£¨t£¬2t-8£©´úÈëy=-x+gµÃ2t-8=-t+g£¬¼´g=3t-8£¬PE½âÎöʽΪy=-x+3t-8£¬Çó³öPµã×ø±êΪ£¨3t-8£¬0£©£¬ÁгöS¡÷DPE=[4-£¨3t-8£©][4-8+2t]=-6t2+36t-48¼´¿ÉÇó½â£»
£¨3£©¶þ´Îº¯Êý¶Ô³ÆÖáΪx=1£¬ÔòC£¨0£¬-4£©¹ØÓÚx=1µÄ¶Ô³ÆµãΪC¡ä£¨2£¬-4£©£¬G£¨0£¬-2£©¹ØÓÚxÖáµÄ¶Ô³ÆµãΪG¡ä£¨0£¬2£©£®Á¬½ÓC¡äG¡ä£¬Óël½»µã¼´ÎªM£¬ÓëxÖá½»µã¼´ÎªN£®´ËʱËıßÐÎCMNGµÄÖܳ¤×îСֵ=C¡äG¡ä£®Çó³öC¡äG¡ä½âÎöʽ¼´¿É½â´ð£®
½â´ð ½â£º£¨1£©µ±x=-1ºÍx=3ʱ£¬¶þ´Îº¯ÊýµÄÖµyÏàµÈ¿ÉÖª¶Ô³ÆÖáΪx=$\frac{-1+3}{2}$=1£¬
¡ßµãAµÄ×ø±êΪ£¨-2£¬0£©£¬
¡àBµã×ø±êΪ£¨4£¬0£©£¬![]()
½«A£¨-2£¬0£©£¬B£¨4£¬0£©·Ö±ð´úÈë½âÎöʽµÃ£¬
$\left\{\begin{array}{l}4a-2b-4=0\\ 16a+4b-4=0\end{array}\right.$£¬
½âµÃ$\left\{\begin{array}{l}a=\frac{1}{2}\\ b=-1\end{array}\right.$£®
¶þ´Îº¯Êý½âÎöʽΪy=$\frac{1}{2}$x2-x-4£®
£¨2£©Èçͼ1£¬×÷EF¡ÍxÖáÓÚF£¬½«µãD£¨2£¬m£©´úÈëy=$\frac{1}{2}$x2-x-4µÃ£¬m=-4£¬
ÔòDµã×ø±êΪ£¨2£¬-4£©£¬
ÉèAD½âÎöʽΪy=kx+b£¬
°ÑA£¨-2£¬0£©£¬D£¨2£¬-4£©·Ö±ð´úÈë½âÎöʽµÃ£¬$\left\{\begin{array}{l}-2k+b=0\\ 2k+b=-4\end{array}\right.$£¬½âµÃ£¬$\left\{\begin{array}{l}b=-2\\ k=-1\end{array}\right.$£¬
º¯ÊýAD½âÎöʽΪy=-x-2£®
¡ßPE¡ÎAD£¬
¡àPE½âÎöʽΪy=-x+g£®
ÉèBD½âÎöʽΪy=mx+n£¬
°ÑB£¨4£¬0£©£¬D£¨2£¬-4£©·Ö±ð´úÈë½âÎöʽµÃ£¬$\left\{\begin{array}{l}4m+n=0\\ 2m+n=-4\end{array}\right.$£¬½âµÃ£¬$\left\{\begin{array}{l}m=2\\ n=-8\end{array}\right.$£¬
º¯ÊýBD½âÎöʽΪy=2x-8£®
Ôò¿ÉÉèE£¨t£¬2t-8£©£¬½«E£¨t£¬2t-8£©´úÈëy=-x+gµÃ2t-8=-t+g£¬¼´g=3t-8£¬
PE½âÎöʽΪy=-x+3t-8£¬![]()
µ±y=0ʱ£¬x=3t-8£¬ÔòPµã×ø±êΪ£¨3t-8£¬0£©£¬
S¡÷DPE=[4-£¨3t-8£©][4-8+2t]=-6t2+36t-48£¬
µ±t=-$\frac{36}{2¡Á£¨-6£©}$=3ʱ£¬S¡÷DPEµÄÃæ»ý×î´ó£¬
´Ëʱ£¬3t-8=3¡Á3-8=1£¬
µÃP£¨1£¬0£©£®
£¨3£©Èçͼ2£¬¶þ´Îº¯Êý¶Ô³ÆÖáΪx=1£¬ÔòC£¨0£¬-4£©¹ØÓÚx=1µÄ¶Ô³ÆµãΪC¡ä£¨2£¬-4£©£¬G£¨0£¬-2£©¹ØÓÚxÖáµÄ¶Ô³ÆµãΪG¡ä£¨0£¬2£©£®
Á¬½ÓC¡äG¡ä£¬Óël½»µã¼´ÎªM£¬ÓëxÖá½»µã¼´ÎªN£®
´ËʱËıßÐÎCMNGµÄÖܳ¤×îСֵ=C¡äG¡ä£®
ÉèC¡äG¡äµÄ½âÎöʽΪy=zx+s£¬
½«C¡ä£¨2£¬-4£©£¬G¡ä£¨0£¬2£©·Ö±ð´úÈë½âÎöʽµÃ£¬$\left\{\begin{array}{l}2z+s=-4\\ s=2\end{array}\right.$£¬
½âµÃ£¬$\left\{\begin{array}{l}z=-3\\ s=2\end{array}\right.$£¬
C¡äG¡äµÄ½âÎöʽΪy=-3x+2£¬
µ±x=1ʱ£¬y=-1£¬M£¨1£¬-1£©£¬
µ±y=0ʱ£¬x=$\frac{2}{3}$£¬N£¨$\frac{2}{3}$£¬0£©£®
ËıßÐÎCMNGµÄÖܳ¤×îСֵ=C¡äG¡ä+CG=$\sqrt{£¨0-2£©^{2}+£¨2+4£©^{2}}$+2=2$\sqrt{10}$+2£®
µãÆÀ ±¾Ì⿼²éÁ˶þ´Îº¯Êý×ÛºÏÌâ£¬Éæ¼°´ý¶¨ÏµÊý·¨ÇóÒ»´Îº¯Êý½âÎöʽ¡¢¶þ´Îº¯Êý½âÎöʽ£¬¶þ´Îº¯ÊýÇó×îÖµ¡¢Öá¶Ô³Æ×î¶Ì·¾¶ÎÊÌ⣬ÄѶȽϴó£¬ÖµµÃ¹Ø×¢£®
| Äê¼¶ | ¸ßÖÐ¿Î³Ì | Äê¼¶ | ³õÖÐ¿Î³Ì |
| ¸ßÒ» | ¸ßÒ»Ãâ·Ñ¿Î³ÌÍÆ¼ö£¡ | ³õÒ» | ³õÒ»Ãâ·Ñ¿Î³ÌÍÆ¼ö£¡ |
| ¸ß¶þ | ¸ß¶þÃâ·Ñ¿Î³ÌÍÆ¼ö£¡ | ³õ¶þ | ³õ¶þÃâ·Ñ¿Î³ÌÍÆ¼ö£¡ |
| ¸ßÈý | ¸ßÈýÃâ·Ñ¿Î³ÌÍÆ¼ö£¡ | ³õÈý | ³õÈýÃâ·Ñ¿Î³ÌÍÆ¼ö£¡ |
¿ÆÄ¿£º³õÖÐÊýѧ À´Ô´£º ÌâÐÍ£º½â´ðÌâ
²é¿´´ð°¸ºÍ½âÎö>>
¿ÆÄ¿£º³õÖÐÊýѧ À´Ô´£º ÌâÐÍ£ºÌî¿ÕÌâ
²é¿´´ð°¸ºÍ½âÎö>>
¿ÆÄ¿£º³õÖÐÊýѧ À´Ô´£º ÌâÐÍ£ºÌî¿ÕÌâ
²é¿´´ð°¸ºÍ½âÎö>>
¿ÆÄ¿£º³õÖÐÊýѧ À´Ô´£º ÌâÐÍ£º½â´ðÌâ
²é¿´´ð°¸ºÍ½âÎö>>
¿ÆÄ¿£º³õÖÐÊýѧ À´Ô´£º ÌâÐÍ£ºÑ¡ÔñÌâ
| A£® | B£® | C£® | D£® |
²é¿´´ð°¸ºÍ½âÎö>>
¿ÆÄ¿£º³õÖÐÊýѧ À´Ô´£º ÌâÐÍ£º½â´ðÌâ
²é¿´´ð°¸ºÍ½âÎö>>
¿ÆÄ¿£º³õÖÐÊýѧ À´Ô´£º ÌâÐÍ£º½â´ðÌâ
²é¿´´ð°¸ºÍ½âÎö>>
¹ú¼ÊѧУÓÅÑ¡ - Á·Ï°²áÁбí - ÊÔÌâÁбí
ºþ±±Ê¡»¥ÁªÍøÎ¥·¨ºÍ²»Á¼ÐÅÏ¢¾Ù±¨Æ½Ì¨ | ÍøÉÏÓк¦ÐÅÏ¢¾Ù±¨×¨Çø | µçÐÅթƾٱ¨×¨Çø | ÉæÀúÊ·ÐéÎÞÖ÷ÒåÓк¦ÐÅÏ¢¾Ù±¨×¨Çø | ÉæÆóÇÖȨ¾Ù±¨×¨Çø
Î¥·¨ºÍ²»Á¼ÐÅÏ¢¾Ù±¨µç»°£º027-86699610 ¾Ù±¨ÓÊÏ䣺58377363@163.com