13£®x2+£¨p+q£©x+pqÐÍʽ×ÓµÄÒòʽ·Ö½â
¡ßx2+£¨p+q£©x+pq=x2+px+qx+pq
=£¨x2+px£©+£¨qx+pq£©£¨¼Ó·¨½áºÏÂÉ£©
=x£¨x+p£©+q£¨x+p£©
=£¨x+p£©£¨x+q£©
¡àÎÒÃǵõ½x2+£¨p+q£©x+pq=£¨x+p£©£¨x+q£©¢Ù
ÀûÓâÙʽ¿ÉÒÔ½«Ä³Ð©¶þ´ÎÏîϵÊýΪ1µÄ¶þ´ÎÈýÏîʽ·Ö½âÒòʽ£®
Àý°Ñx2+3x+2·Ö½âÒòʽ
·ÖÎö£ºx2+3x+2ÖеĶþ´ÎÏîϵÊýΪ1£¬³£ÊýÏî2=1¡Á2£¬Ò»´ÎÏîϵÊý3=1+2£¬ÕâÊÇÒ»¸öx2+£¨p+q£©x+pqÐÍʽ×Ó£®
¡à½â£ºx2+3x+2=£¨x+1£©£¨x+2£©
Çë·ÂÕÕÉÏÃæµÄ·½·¨½«ÏÂÁжàÏîʽ·Ö½âÒòʽ£º
¢Ùx2+7x+10=£¨x+2£©£¨x+5£©£»¡¡¡¡¡¡¢Úx2-2y-8=£¨y-4£©£¨y+2£©£®

·ÖÎö ¸ù¾Ýx2+£¨p+q£©x+pq=£¨x+p£©£¨x+q£©ÈÝÒ׵óö´ð°¸£®

½â´ð ½â£º¢Ùx2+7x+10=£¨x+2£©£¨x+5£©£»
¹Ê´ð°¸Îª£º£¨x+2£©£¨x+5£©£»
¢Úx2-2y-8=£¨y-4£©£¨y+2£©£»
¹Ê´ð°¸Îª£º£¨y-4£©£¨y+2£©£®

µãÆÀ ±¾Ì⿼²éÁËÒòʽ·Ö½âµÄ·½·¨£»ÊìÁ·ÕÆÎÕx2+£¨p+q£©x+pq=£¨x+p£©£¨x+q£©Êǽâ¾öÎÊÌâµÄ¹Ø¼ü£®

Á·Ï°²áϵÁдð°¸
Ïà¹ØÏ°Ìâ

¿ÆÄ¿£º³õÖÐÊýѧ À´Ô´£º ÌâÐÍ£ºÌî¿ÕÌâ

15£®Ì«¼«ÊÇÖйúÎÄ»¯Ê·ÉϵÄÒ»¸öÖØÒª¸ÅÄÈçͼÊÇÌ«¼«Í¼£¬ÊÇÒÔ´óÔ²Ö±¾¶AB·Ö±ðÏò×óÓÒ×÷Á½¸ö°ëÔ²¶ø³É£¬ÈôAB=10cm£¬¼Ç$\widehat{ADB}$£¬$\widehat{AEO}$£¬$\widehat{BFO}$µÄ³¤·Ö±ðΪl1£¬l2£¬l3£¬Ôòl1+l2+l3=10¦Ðcm£®

²é¿´´ð°¸ºÍ½âÎö>>

¿ÆÄ¿£º³õÖÐÊýѧ À´Ô´£º ÌâÐÍ£º½â´ðÌâ

16£®£¨1£©¼ÆË㣺£¨2x+1£©£¨x-4£©-£¨7-x£©£¨-7-x£©
£¨2£©ÏÈ»¯¼ò£¬ÔÙÇóÖµ£º£¨$\frac{5m-4n}{2}$£©2-£¨$\frac{5m+4n}{2}$£©2+10mn£¬ÆäÖÐm=2£¬n=-$\frac{1}{5}$£®

²é¿´´ð°¸ºÍ½âÎö>>

¿ÆÄ¿£º³õÖÐÊýѧ À´Ô´£º ÌâÐÍ£ºÌî¿ÕÌâ

8£®ÎÒÃdzÆʹ$\frac{a}{2}$+$\frac{b}{3}$=$\frac{a+b}{2+3}$³ÉÁ¢µÄÒ»¶ÔÊýa£¬bΪ¡°Ïà°éÊý¶Ô¡±£¬¼ÇΪ£¨a£¬b£©£¬È磺µ±a=b=0ʱ£¬µÈʽ³ÉÁ¢£¬¼ÇΪ£¨0£¬0£©£®Èô£¨a£¬3£©ÊÇ¡°Ïà°éÊý¶Ô¡±£¬ÔòaµÄֵΪ-$\frac{4}{3}$£®

²é¿´´ð°¸ºÍ½âÎö>>

¿ÆÄ¿£º³õÖÐÊýѧ À´Ô´£º ÌâÐÍ£º½â´ðÌâ

18£®Èçͼ£¬Ö±ÏßlÓëxÖᣬyÖá·Ö±ð½»ÓÚM£¬NÁ½µã£¬ÇÒOM=ON=3£®
£¨1£©ÇóÕâÌõÖ±Ïߵĺ¯Êý±í´ïʽ£»
£¨2£©Rt¡÷ABCÓëÖ±ÏßlÔÚͬһ¸öƽÃæÖ±½Ç×ø±êϵÄÚ£¬ÆäÖСÏABC=90¡ã£¬AC=2$\sqrt{5}$£¬A£¨1£¬0£©£¬B£¨3£¬0£©£¬½«¡÷ABCÑØ×ÅxÖáÏò×óƽÒÆ£¬µ±µãCÂäÔÚÖ±ÏßlÉÏʱ£¬ÇóÏ߶ÎACɨ¹ýµÄÃæ»ý£®

²é¿´´ð°¸ºÍ½âÎö>>

¿ÆÄ¿£º³õÖÐÊýѧ À´Ô´£º ÌâÐÍ£ºÑ¡ÔñÌâ

2£®µãA£¨-1£¬4£©¹ØÓÚxÖá¶Ô³ÆµÄµãµÄ×ø±êΪ£¨¡¡¡¡£©
A£®£¨1£¬4£©B£®£¨-1£¬-4£©C£®£¨1£¬-4£©D£®£¨4£¬-1£©

²é¿´´ð°¸ºÍ½âÎö>>

¿ÆÄ¿£º³õÖÐÊýѧ À´Ô´£º ÌâÐÍ£ºÌî¿ÕÌâ

3£®Èçͼ£¬¡÷ABCÖУ¬AB=12£¬AC=8£¬AD¡¢AE·Ö±ðÊÇÆä½Çƽ·ÖÏߺÍÖÐÏߣ¬¹ýµãC×÷CG¡ÍADÓÚF£¬½»ABÓÚG£¬Á¬½ÓEF£¬ÔòÏ߶ÎEFµÄ³¤Îª2£®

²é¿´´ð°¸ºÍ½âÎö>>

ͬ²½Á·Ï°²á´ð°¸