7£®ÇúÏßC1µÄ²ÎÊý·½³ÌΪ$\left\{\begin{array}{l}{x=2+2cos¦Á}\\{y=2sin¦Á}\end{array}\right.$£¨¦ÁΪ²ÎÊý£©ÔÚÒÔÔ­µãOΪ¼«µã£¬xÖáµÄ·Ç¸º°ëÖáΪ¼«ÖáµÄ¼«×ø±êϵÖУ¬ÇúÏßC2µÄ¼«×ø±ê·½³ÌΪ¦Ñcos2¦È=sin¦È£®
£¨1£©ÇóÇúÏßC1µÄ¼«×ø±ê·½³ÌºÍÇúÏßC2µÄÖ±½Ç×ø±ê·½³Ì£»
£¨2£©¹ýÔ­µãÇÒÇãб½ÇΪ¦Á£¨$\frac{¦Ð}{6}$£¼¦Á¡Ü$\frac{¦Ð}{4}$£©µÄÉäÏßlÓëÇúÏßC1£¬C2·Ö±ðÏཻÓÚA£¬BÁ½µã£¨A£¬BÒìÓÚÔ­µã£©£¬Çó|OA|•|OB|µÄÈ¡Öµ·¶Î§£®

·ÖÎö £¨1£©ÏȽ«C1µÄ²ÎÊý·½³Ì»¯ÎªÆÕͨ·½³Ì£¬ÔÙ»¯Îª¼«×ø±ê·½³Ì£¬½«C2µÄ¼«×ø±ê·½³ÌÁ½±ßͬ³Ë¦Ñ£¬¸ù¾Ý¼«×ø±êÓëÖ±½Ç×ø±êµÄ¶ÔÓ¦¹ØϵµÃ³öC2µÄÖ±½Ç×ø±ê·½³Ì£»
£¨2£©Çó³ölµÄ²ÎÊý·½³Ì£¬·Ö±ð´úÈëC1£¬C2µÄÆÕͨ·½³Ì£¬¸ù¾Ý²ÎÊýµÄ¼¸ºÎÒâÒåµÃ³ö|OA|£¬|OB|£¬µÃµ½|OA|•|OB|¹ØÓÚkµÄº¯Êý£¬¸ù¾ÝkµÄ·¶Î§µÃ³ö´ð°¸£®

½â´ð ½â£º£¨1£©ÇúÏßC1µÄ²ÎÊý·½³ÌΪ$\left\{\begin{array}{l}{x=2+2cos¦Á}\\{y=2sin¦Á}\end{array}\right.$£¨¦ÁΪ²ÎÊý£©£¬ÆÕͨ·½³ÌΪ£¨x-2£©2+y2=4£¬¼´x2+y2=4x£¬¼«×ø±ê·½³ÌΪ¦Ñ=4cos¦È£»ÇúÏßC1µÄ¼«×ø±ê·½³ÌΪ¦Ñcos2¦È=sin¦È£¬ÆÕͨ·½³ÌΪ£ºy=x2£»
£¨2£©ÉäÏßlµÄ²ÎÊý·½³ÌΪ$\left\{\begin{array}{l}{x=tcos¦Á}\\{y=tsin¦Á}\end{array}\right.$£¨tΪ²ÎÊý£¬$\frac{¦Ð}{6}$£¼¦Á¡Ü$\frac{¦Ð}{4}$£©£®
°ÑÉäÏßlµÄ²ÎÊý·½³Ì´úÈëÇúÏßC1µÄÆÕͨ·½³ÌµÃ£ºt2-4tcos¦Á=0£¬
½âµÃt1=0£¬t2=4cos¦Á£®
¡à|OA|=|t2|=4cos¦Á£®
°ÑÉäÏßlµÄ²ÎÊý·½³Ì´úÈëÇúÏßC2µÄÆÕͨ·½³ÌµÃ£ºcos2¦Át2=tsin¦Á£¬
½âµÃt1=0£¬t2=$\frac{sin¦Á}{co{s}^{2}¦Á}$£®
¡à|OB|=|t2|=$\frac{sin¦Á}{co{s}^{2}¦Á}$£®
¡à|OA|•|OB|=4cos¦Á•$\frac{sin¦Á}{co{s}^{2}¦Á}$=4tan¦Á=4k£®
¡ßk¡Ê£¨$\frac{\sqrt{3}}{3}$£¬1]£¬¡à4k¡Ê£¨$\frac{4\sqrt{3}}{3}$£¬4]£®
¡à|OA|•|OB|µÄÈ¡Öµ·¶Î§ÊÇ£¨$\frac{4\sqrt{3}}{3}$£¬4]£®

µãÆÀ ±¾Ì⿼²é²ÎÊý·½³ÌÓ뼫×ø±êÓëÆÕͨ·½³ÌµÄ»¥»¯£¬¿¼²é²ÎÊýµÄ¼¸ºÎÒâÒåµÄÓ¦Óã¬ÊôÓÚÖеµÌ⣮

Á·Ï°²áϵÁдð°¸
Ïà¹ØÏ°Ìâ

¿ÆÄ¿£º¸ßÖÐÊýѧ À´Ô´£º ÌâÐÍ£ºÑ¡ÔñÌâ

17£®Èç¹ûÖ´ÐÐÈçͼËùʾµÄ³ÌÐò¿òͼ£¬ÈôÊä³öµÄÊýi=4£¬ÔòÊäÈëµÄxµÄÈ¡Öµ·¶Î§ÊÇ£¨¡¡¡¡£©
A£®[3£¬4£©B£®£¨3£¬4]C£®[4£¬5£©D£®£¨4£¬5]

²é¿´´ð°¸ºÍ½âÎö>>

¿ÆÄ¿£º¸ßÖÐÊýѧ À´Ô´£º ÌâÐÍ£º½â´ðÌâ

18£®ÔÚ¡÷ABCÖУ¬a£¬b£¬c·Ö±ðÊǽÇA£¬B£¬CµÄ¶Ô±ß£¬ÏòÁ¿$\overrightarrow{m}$=£¨cos£¨A-B£©£¬sin£¨A-B£©£©£¬$\overrightarrow{n}$=£¨cosB£¬-sinB£©£¬ÇÒ $\overrightarrow{m}$•$\overrightarrow{n}$=-$\frac{3}{5}$£®
£¨¢ñ£©ÇósinAµÄÖµ£»
£¨¢ò£©Èôa=4$\sqrt{2}$£¬b=5£¬Çó½ÇBµÄ´óС¼°ÏòÁ¿$\overrightarrow{AB}$ÔÚ$\overrightarrow{BC}$·½ÏòÉϵÄͶӰ£®

²é¿´´ð°¸ºÍ½âÎö>>

¿ÆÄ¿£º¸ßÖÐÊýѧ À´Ô´£º ÌâÐÍ£ºÌî¿ÕÌâ

15£®Éè[x]±íʾ²»´óÓÚxµÄ×î´óÕûÊý£¬¼¯ºÏA={x|[x]2-2[x]=3}£¬B={x|2x£¾8}£¬ÔòA¡ÉB=£¨3£¬4£©£®

²é¿´´ð°¸ºÍ½âÎö>>

¿ÆÄ¿£º¸ßÖÐÊýѧ À´Ô´£º ÌâÐÍ£ºÌî¿ÕÌâ

2£®ÔÚÀⳤΪ3µÄÕý·½ÌåABCD-A1B1C1D1ÄÚ²¿Ëæ»úÈ¡Ò»¸öµãM£¬ÔòµãMµ½¶¥µãAµÄ¾àÀ볬¹ý1µÄ¸ÅÂÊΪ$1-\frac{¦Ð}{162}$£®

²é¿´´ð°¸ºÍ½âÎö>>

¿ÆÄ¿£º¸ßÖÐÊýѧ À´Ô´£º ÌâÐÍ£ºÑ¡ÔñÌâ

12£®ÒÑÖªµÈ²îÊýÁÐ{an}Âú×ãa1+a2=-1£¬a3=4£¬Ôòa4+a5=£¨¡¡¡¡£©
A£®17B£®16C£®15D£®14

²é¿´´ð°¸ºÍ½âÎö>>

¿ÆÄ¿£º¸ßÖÐÊýѧ À´Ô´£º ÌâÐÍ£ºÑ¡ÔñÌâ

19£®Ö´ÐÐÈçͼËùʾµÄ³ÌÐò¿òͼ£¬Êä³öµÄyֵΪ£¨¡¡¡¡£©
A£®15B£®17C£®19D£®21

²é¿´´ð°¸ºÍ½âÎö>>

¿ÆÄ¿£º¸ßÖÐÊýѧ À´Ô´£º ÌâÐÍ£ºÑ¡ÔñÌâ

16£®¶¨ÒåÔËËã$|{\begin{array}{l}a&b\\ c&d\end{array}}|=ad-bc$£¬Ôò·ûºÏÌõ¼þ$|{\begin{array}{l}z&{1+i}\\{-i}&{2i}\end{array}}|=0$µÄ¸´ÊýzµÄ¹²éÊý$\overline z$ÔÚ¸´Æ½ÃæÄÚ¶ÔÓ¦µÄµãÔÚ£¨¡¡¡¡£©
A£®µÚÒ»ÏóÏÞB£®µÚ¶þÏóÏÞC£®µÚÈýÏóÏÞD£®µÚËÄÏóÏÞ

²é¿´´ð°¸ºÍ½âÎö>>

¿ÆÄ¿£º¸ßÖÐÊýѧ À´Ô´£º ÌâÐÍ£ºÑ¡ÔñÌâ

17£®ÒÑÖªµãPÔÚº¯Êý$f£¨x£©=ln£¨{2x+1}£©+\frac{{{x^2}+x}}{8}$ͼÏóÉÏ£¬Ôòº¯Êýf£¨x£©ÔÚµãP´¦ÇÐÏßÇãб½Ç¦ÁµÄÈ¡Öµ·¶Î§£¨¡¡¡¡£©
A£®$[{\frac{¦Ð}{4}£¬\frac{¦Ð}{2}}£©$B£®$[{\frac{¦Ð}{4}£¬\frac{3¦Ð}{4}}]$C£®$[{\frac{¦Ð}{4}£¬¦Ð}£©$D£®$[{0£¬\frac{¦Ð}{4}}]$

²é¿´´ð°¸ºÍ½âÎö>>

ͬ²½Á·Ï°²á´ð°¸