14£®ÔÚÆ½ÃæÖ±½Ç×ø±êϵxOyÖУ¬ÇúÏßCµÄ²ÎÊý·½³ÌΪ$\left\{{\begin{array}{l}{x=2cos¦Á}\\{y=sin¦Á}\end{array}}\right.£¨¦ÁΪ²ÎÊý£©$£¬Ö±ÏßlµÄ²ÎÊý·½³ÌΪ$\left\{{\begin{array}{l}{x=\frac{3}{5}t}\\{y=4+\frac{4}{5}t}\end{array}£¨tΪ²ÎÊý£©}\right.$£®ÒÔ×ø±êÔ­µãΪ¼«µã£¬xÖáµÄ·Ç¸º°ëÖáΪ¼«ÖὨÁ¢¼«×ø±êϵ£®
£¨1£©ÇóÇúÏßCµÄÖ±½Ç×ø±ê·½³ÌºÍÖ±ÏßlµÄ¼«×ø±ê·½³Ì£»
£¨2£©ÈôP£¨x£¬y£©ÎªÇúÏßCÉϵ͝µã£¬ÇóµãPµ½Ö±ÏßlµÄ¾àÀëdµÄ×î´óÖµºÍ×îСֵ£®

·ÖÎö £¨1£©ÓÉÇúÏßCµÄ²ÎÊý·½³ÌΪ$\left\{{\begin{array}{l}{x=2cos¦Á}\\{y=sin¦Á}\end{array}}\right.£¨¦ÁΪ²ÎÊý£©$£¬ÀûÓÃcos2¦Á+sin2¦Á=1¿ÉµÃÇúÏßCµÄÖ±½Ç×ø±ê·½³Ì£®ÓÉÖ±ÏßlµÄ²ÎÊý·½³ÌΪ$\left\{{\begin{array}{l}{x=\frac{3}{5}t}\\{y=4+\frac{4}{5}t}\end{array}£¨tΪ²ÎÊý£©}\right.$£®ÏûÈ¥²ÎÊýt¿ÉµÃ£ºÖ±ÏßlµÄÖ±½Ç×ø±ê·½³Ì£¬°Ñ$\left\{\begin{array}{l}{x=¦Ñcos¦È}\\{y=¦Ñsin¦È}\end{array}\right.$´úÈë¿ÉµÃ¼«×ø±ê·½³Ì£®
£¨2£©ÉèP£¨2cos¦Á£¬sin¦Á£©£¬Ö±ÏßlΪ4x-3y+12=0£¬ÀûÓõ㵽ֱÏߵľàÀ빫ʽ¡¢Èý½Çº¯ÊýµÄµ¥µ÷ÐÔ¼´¿ÉµÃ³ö£®

½â´ð ½â£º£¨1£©ÓÉÇúÏßCµÄ²ÎÊý·½³ÌΪ$\left\{{\begin{array}{l}{x=2cos¦Á}\\{y=sin¦Á}\end{array}}\right.£¨¦ÁΪ²ÎÊý£©$£¬ÀûÓÃcos2¦Á+sin2¦Á=1¿ÉµÃ£ºÇúÏßCµÄÖ±½Ç×ø±ê·½³ÌΪ$\frac{x^2}{4}+{y^2}=1$£®
ÓÉÖ±ÏßlµÄ²ÎÊý·½³ÌΪ$\left\{{\begin{array}{l}{x=\frac{3}{5}t}\\{y=4+\frac{4}{5}t}\end{array}£¨tΪ²ÎÊý£©}\right.$£®ÏûÈ¥²ÎÊýt¿ÉµÃ£ºÖ±ÏßlµÄÖ±½Ç×ø±ê·½³ÌΪ4x-3y+12=0£¬
°Ñ$\left\{\begin{array}{l}{x=¦Ñcos¦È}\\{y=¦Ñsin¦È}\end{array}\right.$´úÈë¿ÉµÃ£º¼«×ø±ê·½³ÌΪ4¦Ñcos¦È-3¦Ñsin¦È+12=0£®
£¨2£©ÉèP£¨2cos¦Á£¬sin¦Á£©£¬Ö±ÏßlΪ4x-3y+12=0£¬
Ôò$d=\frac{{|{8cos¦Á-3sin¦Á+12}|}}{5}=\frac{{|{\sqrt{73}cos£¨¦Á+?£©+12}|}}{5}$£¬
¡à×î´óֵΪ$\frac{{12+\sqrt{73}}}{5}$£¬×îСֵΪ$\frac{{12-\sqrt{73}}}{5}$£®

µãÆÀ ±¾Ì⿼²éÁ˲ÎÊý·½³Ì»¯ÎªÆÕͨ·½³Ì¡¢¼«×ø±ê·½³ÌÓëÖ±½Ç×ø±ê·½³Ì»¥»¯¡¢ÍÖÔ²µÄ²ÎÊý·½³Ì¡¢µãµ½Ö±ÏߵľàÀ빫ʽ¡¢Èý½Çº¯ÊýµÄµ¥µ÷ÐÔ£¬¿¼²éÁËÍÆÀíÄÜÁ¦Óë¼ÆËãÄÜÁ¦£¬ÊôÓÚÖеµÌ⣮

Á·Ï°²áϵÁдð°¸
Ïà¹ØÏ°Ìâ

¿ÆÄ¿£º¸ßÖÐÊýѧ À´Ô´£º ÌâÐÍ£º½â´ðÌâ

4£®4ÔÂ23ÈËÊÇ¡°ÊÀ½ç¶ÁÊéÈÕ¡±£¬Ä³ÖÐѧÔÚ´ËÆÚ¼ä¿ªÕ¹ÁËһϵÁеĶÁÊé½ÌÓý»î¶¯£¬ÎªÁ˽ⱾУѧÉú¿ÎÍâÔĶÁÇé¿ö£¬Ñ§Ð£Ëæ»ú³éÈ¡ÁË100ÃûѧÉú¶ÔÆä¿ÎÍâÔĶÁʱ¼ä½øÐе÷²é£¬ÏÂÃæÊǸù¾Ýµ÷²é½á¹û»æÖƵÄѧÉúÈÕ¾ù¿ÎÍâÔĶÁʱ¼ä£¨µ¥Î»£º·ÖÖÓ£©µÄƵÂÊ·Ö²¼Ö±·½Í¼£¬Èô½«ÈÕ¾ù¿ÎÍâÔĶÁʱ¼ä²»µÍÓÚ60·ÖÖÓµÄѧÉú³ÆÎª¡°¶ÁÊéÃÕ¡±£¬µÍÓÚ60·ÖÖÓµÄѧÉú³ÆÎª¡°·Ç¶ÁÊéÃÕ¡±

£¨1£©¸ù¾ÝÒÑÖªÌõ¼þÍê³ÉÏÂÃæ2¡Á2µÄÁÐÁª±í£¬²¢¾Ý´ËÅжÏÊÇ·ñÓÐ99%µÄ°ÑÎÕÈÏΪ¡°¶ÁÊéÃÕ¡±ÓëÐÔ±ðÓйأ¿
·Ç¶ÁÊéÃÔ¶ÁÊéÃԺϼÆ
ÄÐ15
Ů45
ºÏ¼Æ
£¨2£©½«ÆµÂÊÊÓΪ¸ÅÂÊ£¬ÏÖÔÚ´Ó¸ÃУ´óÁ¿Ñ§ÉúÖУ¬ÓÃËæ»ú³éÑùµÄ·½·¨Ã¿´Î³éÈ¡1ÈË£¬¹²³éÈ¡3´Î£¬¼Ç±»³éÈ¡µÄ3ÈËÖеġ°¶ÁÊéÃÕ¡±µÄÈËÊýΪX£¬Èôÿ´Î³éÈ¡µÄ½á¹ûÊÇÏ໥¶ÀÁ¢µÄ£¬ÇóXµÄ·Ö²¼ÁУ¬ÆÚÍûE£¨X£©ºÍ·½³ÌD£¨X£©
¸½£ºK2=$\frac{n£¨ad-bc£©^{2}}{£¨a+b£©£¨c+d£©£¨a+c£©£¨b+d£©}$n=a+b+c+d
P£¨K2¡Ýk0£©0.1000.0500.0250.0100.001
k02.7063.8415.0246.63510.828

²é¿´´ð°¸ºÍ½âÎö>>

¿ÆÄ¿£º¸ßÖÐÊýѧ À´Ô´£º ÌâÐÍ£ºÌî¿ÕÌâ

5£®ÈôÖ¸Êýº¯Êýf£¨x£©µÄͼÏó¹ýµã£¨-2£¬4£©£¬Ôòf£¨3£©=$\frac{1}{8}$£»²»µÈʽf£¨x£©+f£¨-x£©£¼$\frac{5}{2}$µÄ½â¼¯Îª£¨-1£¬1£©£®

²é¿´´ð°¸ºÍ½âÎö>>

¿ÆÄ¿£º¸ßÖÐÊýѧ À´Ô´£º ÌâÐÍ£ºÑ¡ÔñÌâ

2£®°Ñº¯Êýf£¨x£©=sin£¨2x+ϕ£©$£¨|ϕ|£¼\frac{¦Ð}{2}£©$µÄͼÏóÏò×óÆ½ÒÆ$\frac{¦Ð}{6}$¸öµ¥Î»£¬µÃµ½º¯Êýg£¨x£©µÄͼÏó£¬Èôg£¨x£©µÄͼÏó¹ØÓÚ$£¨-\frac{¦Ð}{3}£¬0£©$¶Ô³Æ£¬Ôò$f£¨-\frac{¦Ð}{2}£©$=£¨¡¡¡¡£©
A£®$-\frac{1}{2}$B£®$\frac{1}{2}$C£®$-\frac{{\sqrt{3}}}{2}$D£®$\frac{{\sqrt{3}}}{2}$

²é¿´´ð°¸ºÍ½âÎö>>

¿ÆÄ¿£º¸ßÖÐÊýѧ À´Ô´£º ÌâÐÍ£ºÌî¿ÕÌâ

9£®ÒÑ֪ʵÊýx£¬yÂú×ã$\left\{{\begin{array}{l}{2x-y+4¡Ý0}\\{x-y+3¡Ý0}\\{x¡Ü0}\\{y¡Ý0}\end{array}}\right.$£¬ÔòÄ¿±êº¯Êýz=3y-2xµÄ×î´óֵΪ9£®

²é¿´´ð°¸ºÍ½âÎö>>

¿ÆÄ¿£º¸ßÖÐÊýѧ À´Ô´£º ÌâÐÍ£ºÌî¿ÕÌâ

19£®ÔÚ¿Õ¼äËıßÐÎABCDÖУ¬µãE£¬F·Ö±ðÊÇAC£¬BDµÄÖеãAB=CD=6£¬ABÓëCDËù³ÉµÄ½ÇΪ60¶È£¬ÔòEFµÄ³¤Îª$3»ò3\sqrt{3}$£®

²é¿´´ð°¸ºÍ½âÎö>>

¿ÆÄ¿£º¸ßÖÐÊýѧ À´Ô´£º ÌâÐÍ£º½â´ðÌâ

6£®¼ÆË㣺¡Òe-2xdx£®

²é¿´´ð°¸ºÍ½âÎö>>

¿ÆÄ¿£º¸ßÖÐÊýѧ À´Ô´£º ÌâÐÍ£ºÌî¿ÕÌâ

12£®ÒÑÖª$\overrightarrow{a}$¡¢$\overrightarrow{b}$¡¢$\overrightarrow{c}$¶¼Îªµ¥Î»ÏòÁ¿£¬ÆäÖÐ$\overrightarrow{a}$¡¢$\overrightarrow{b}$µÄ¼Ð½ÇΪ$\frac{2}{3}$¦Ð£¬Ôò$\sqrt{1-\overrightarrow{a}•\overrightarrow{b}}$+$\sqrt{1-\overrightarrow{b}•\overrightarrow{c}}$µÄȡֵ·¶Î§ÊÇ[$\frac{\sqrt{6}}{2}$£¬$\frac{\sqrt{6}}{2}$$+\sqrt{2}$]£®

²é¿´´ð°¸ºÍ½âÎö>>

¿ÆÄ¿£º¸ßÖÐÊýѧ À´Ô´£º ÌâÐÍ£ºÑ¡ÔñÌâ

13£®Éèf£¨x£©=$\left\{\begin{array}{l}{x^t}£¬x£¼2\\ 1o{g_t}£¨{x^2}+7£©£¬x¡Ý2\end{array}$£¬Ôò$f£¨\sqrt{2}£©=4$£¬Ôòf£¨3£©=£¨¡¡¡¡£©
A£®2B£®4C£®6D£®8

²é¿´´ð°¸ºÍ½âÎö>>

ͬ²½Á·Ï°²á´ð°¸