14．(坐标系与参数方程选做题)在极坐标系中，直线l的方程为ρsinθ=3，则点(2，π/6)到直线l的距离为　　　　　　 ．

[解析]法1:画出极坐标系易得答案2; 法2:化成直角方程及直角坐标可得答案2.

　 15．(几何证明选讲选做题)如图4所示，圆O的直径AB=6，C为圆周上一点，BC=3过C作圆的切线l，过A作l的垂线AD，垂足为D， 则∠DAC=　　　　 ．

[解析]由某定理可知,又,

故.

(2007海南、宁夏)

15．几何证明选讲选做题］如图所示，圆O的直径为6，C为圆周上一点。BC＝3，过C作圆的切线l，过A作l的垂线AD，垂足为D，则∠DAC＝______；线段AE的长为_______。

答案：；3。

解析：根据弦切角等于夹弧所对的圆周角及直角三角形两锐角互余，很容易得到答案； AE=EC=BC=3；

(2007广东文)

14．(不等式选讲选做题)设函数则=_____；若，则x的取值范围是________；

答案：6；

13．(坐标系与参数方程选做题)在平面直角坐标系xOy 中，直线l的参数方程为(参数t∈R)，圆C的参数方程为(参数)，则圆C的圆心坐标为_______，圆心到直线l的距离为______.

答案：(0，2)；.

解析：直线的方程为x+y-6=0，d=;

70、Can you work out what these squiggles mean?

答案：68、事情的结果很不错。69、我一向无法了解她。70、你能辨认出这些潦草的字迹是什么意思吗？

69、I've never been able to work her out. ________________

(1)　　　 We must work out a plan as quickly as we can.<制定，拟定，定出>

(2)　　　 Have you worked out this problem yet?<算出，估计出>

(3)　　　 I can't work out the meaning of the poem.<理解，弄懂，看出>

(4)　　　 This map is wrong；I can't work out where we are.<判断，说出，看出>

(5)　　　 Things will work out if you will just be patient.<得到圆满解决>

(6)　　　 Things have worked out badly.<(情况等)结果是>

(题组训练)英译汉：

68、Things worked out quite well. ________________

(1)　　　 The assistant did not take her seriously and advised her to buy two bottles of very expensive wine.<认真对待>

(2)　　　 He led the ships down the river to a place where the British army could land safely and take the enemy by surprise.<突然袭击>

(3)　　　 I won't take up much of your time.<占去(时间)>

(4)　　　 The table takes up too much room.<占去，占据(空间)>

(5)　　　 When he left school he took up journalism.<从事某项活动，发展某种爱好>

(6)　　　 People should be ready to go to prison for their beliefs，but they should never take up anus to fight.<拿起武器>

(7)　　　 When you return to the office the following morning or after the holiday，you can listen to the messages and take any necessary action.<采取必要的行动>

(8)　　　 The teacher took up the lesson where he left off yesterday.<继续讲述>

(9)　　　 Jean took advantage of the lunch hour to finish her homework.<利用>

(10)　 I take back what I said.<收回>

(11)　 Take it easy.The roads are icy.<不要着急>

(12)　 He is taking over my job while I am on holiday.<接替，接管>

(13)　 He seemed to take great pride in his work.<对……感到骄傲>

(14)　 She had taken the trouble to buy the books for me.<费力，不怕麻烦>

(15)　 I'll take on the work，but I can't tell you exactly when I'll finish it.<从事>

(16)　 The Great Wall has taken on a new look since the liberation.<呈现>

(17)　 Is the supermarket taking on any more assistants?<雇用>

67、If you don't know the words，you can ________________ (refer to)a dictionary.

答案：65、turned up 66、turned down 67、turn to

66、His invitation is ________________ (refused).