如图圆O的半径为1,点P是圆O上一点,弦AB垂直平分线段OP,点D是弧APB上任一点（与端点A B不重合）,DE⊥AB于点E,以点D为圆心,DE长为半径作圆D,分别过点A、B作圆D的切线,两条切线相交于点C求旋AB长

如图圆O的半径为1,点P是圆O上一点,弦AB垂直平分线段OP,点D是弧APB上任一点（与端点A B不重合）,DE⊥AB于点E,以点D为圆心,DE长为半径作圆D,分别过点A、B作圆D的切线,两条切线相交于点C求旋AB长
如图圆O的半径为1,点P是圆O上一点,弦AB垂直平分线段OP,点D是弧APB上任一点（与端点A B不重合）,DE⊥AB于点E,以点D为圆心,DE长为半径作圆D,分别过点A、B作圆D的切线,两条切线相交于点C
求旋AB长
判断角ACB是否为定值若是求ACB的大小否则请说明理由
图：

如图圆O的半径为1,点P是圆O上一点,弦AB垂直平分线段OP,点D是弧APB上任一点（与端点A B不重合）,DE⊥AB于点E,以点D为圆心,DE长为半径作圆D,分别过点A、B作圆D的切线,两条切线相交于点C求旋AB长
AB=根号3
角ACB是恒定值,且为60°
AB的长度值我在这里就不解释了,就是运用勾股定理计算就可以了.
在这里我稍微解释下角ACB的值
由于D是APB上任一点,所以角ADB的值始终不变,都为120°,因为圆上一根弦对应的圆周角相等.所以 角DBA+角DAB=60° 从而有∠CAB+∠CBA=2 X 60°=120°
所以∠ACB=180°-120°=60°
讲的不够清楚,希望楼主能明白
最后我建议楼主遇到这种问题还是请教老师比较好,网上回答的总是不够彻底!

Prince William's wedding ceremony by the global attention, the United States "OK!" Magazine estimated to cost up to $ 34,000,000,gucci men's shoes, ranking the most expensive wedding. However, the U.S...

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Prince William's wedding ceremony by the global attention, the United States "OK!" Magazine estimated to cost up to $ 34,000,000,gucci men's shoes, ranking the most expensive wedding. However, the U.S. "Star Weekly" royal sources quoted saying Christopher Wilson, 29-year-old Kate and 28-year-old son and heir of William who are charged with continued pressure on the royal family, who have not married before they made a success. Kate has been passed within the palace Wai Fun, "Dragon Seed": "They do not want a late age son, the baby finally report."
The source revealed: "Kate had feared would be the wedding day morning sickness, want to delay the wedding,wholesale oil painting, and finally decided to be held as usual." Magazine also pointed out that the great-grandson of Queen Elizabeth can not wait Xiangbao, do not care about the image of the royal family, willing to open one eye closed one Eye to Kate, "the ball" married. Rumor that Kate has been signed before marriage prenuptial agreement 4 million U.S. dollars, the United States "inTouch" reported that she longed early pregnancy, gave birth to the royal heir,manolo blahnik sandals, so the pressure is too large. It is reported that Prince William's wedding costs were roughly as high as 986 million Taiwan dollars, of which security to the wedding and the guests up to 9 billion New Taiwan dollars. Kate's wedding secret, the magazine speculated that she will wear Emanuel Ungaro design, inlaid with 10,000 pearls, more than 1 million yuan NT white. Another media that she has prepared two sets of wedding, if the preferred style exposure to other models to wear. British "Daily Mail" reported that the wedding would not comb her header, will be covered with long hair flowing veil.
Currently the world's most interesting topic, the earthquake has changed from the Japanese Prince William's wedding, but dozens of Prince William the future king of the Commonwealth countries, so the whole vision of the UK and throughout the world have focused on him, Prince William's wedding present to the final countdown has entered the stage, the whole of British society were all getting ready for the wedding. At the official level, will escort at the wedding of William and Kate Royal Rangers, to perform at the wedding band the Royal Air Force, the main venue for the wedding choir of Westminster Abbey during the last exercise so as to In the wedding day to ensure foolproof. Prince William's fiancee Kate, who was his classmate classmates, not only beautiful and outstanding temperament, has been ranked the most beautiful members of the royal family in the third world, and Queen Elizabeth II at the University of Prince William and Kate met the graduation ceremony for the first time , you are very loved Kate. Since Prince William and girlfriend Kate Middleton classmate's romance came to light, elegant and generous of Kate, won the unanimous recognition of the British royal family members, especially to win the Queen's love.
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