ÌâÄ¿ÄÚÈÝ
1£®ÒÑÖª¿Õ¼ä·ÇÁãÏòÁ¿$\overrightarrow{{s}_{1}}$£¬$\overrightarrow{{s}_{2}}$£¬Ôò¡°cos£¼$\overrightarrow{{s}_{1}}$£¬$\overrightarrow{{s}_{2}}$£¾=$\frac{1}{2}$¡±ÊÇ¡°$\overrightarrow{{s}_{1}}$Óë$\overrightarrow{{s}_{2}}$µÄ¼Ð½ÇΪ$\frac{¦Ð}{3}$¡±µÄ£¨¡¡¡¡£©| A£® | ³ä·Ö²»±ØÒªÌõ¼þ | B£® | ±ØÒª²»³ä·ÖÌõ¼þ | ||
| C£® | ³äÒªÌõ¼þ | D£® | ¼È²»³ä·ÖÒ²²»±ØÒªÌõ¼þ |
·ÖÎö ÓÉÏòÁ¿ºÍÈý½Çº¯ÊýµÄµ¥µ÷ÐÔÒÔ¼°³äÒªÌõ¼þµÄÅж¨¿ÉµÃ£®
½â´ð ½â£º¡ßÏòÁ¿µÄ¼Ð½ÇÔÚ[0£¬¦Ð]£¬ÓàÏÒº¯ÊýÔÚ[0£¬¦Ð]µ¥µ÷µÝ¼õ£¬
½áºÏcos$\frac{¦Ð}{3}$=$\frac{1}{2}$¿ÉµÃ¡°cos£¼$\overrightarrow{{s}_{1}}$£¬$\overrightarrow{{s}_{2}}$£¾=$\frac{1}{2}$¡±ÊÇ¡°$\overrightarrow{{s}_{1}}$Óë$\overrightarrow{{s}_{2}}$µÄ¼Ð½ÇΪ$\frac{¦Ð}{3}$¡±µÄ³äÒªÌõ¼þ£®
¹ÊÑ¡£ºC£®
µãÆÀ ±¾Ì⿼²é³äÒªÌõ¼þµÄÅж¨£¬Éæ¼°ÏòÁ¿ºÍÈý½Çº¯ÊýµÄ֪ʶ£¬Êô»ù´¡Ì⣮
Á·Ï°²áϵÁдð°¸
Ïà¹ØÌâÄ¿
6£®¹ýÔ²x2+y2=4ÉÏÒ»µã£¨$\sqrt{2}$£¬1£©µÄÇÐÏß·½³ÌΪ£¨¡¡¡¡£©
| A£® | x+$\sqrt{2}$y=4 | B£® | $\sqrt{2}$x+y=3 | C£® | $\sqrt{2}$x+y=4 | D£® | x+$\sqrt{2}$y=2 |
14£®ÒÑ֪˫ÇúÏß$\frac{x^2}{a^2}-\frac{y^2}{b^2}=1£¨{a£¾0£¬b£¾0}£©$¾¹ýÒ»¡¢ÈýÏóÏ޵Ľ¥½üÏßΪm£¬ÈôÔ²${x^2}+{y^2}-2\sqrt{5}x-2\sqrt{5}y+6=0$ÉÏÖÁÉÙÓÐÈý¸ö²»Í¬µÄµãµ½mµÄ¾àÀëΪ1£¬Ôò´ËË«ÇúÏßµÄÀëÐÄÂÊeµÄȡֵ·¶Î§Îª£¨¡¡¡¡£©
| A£® | $[{\frac{{\sqrt{5}}}{2}£¬2\sqrt{5}}]$ | B£® | $£¨{1£¬\sqrt{5}}]$ | C£® | $[{\frac{{\sqrt{5}}}{2}£¬\sqrt{5}}]$ | D£® | $[{\sqrt{5}£¬2\sqrt{5}}]$ |