如图,某海轮以每小时30海里的速度航行,在A点测得海面上油井P在南偏东60°,向北航行40分钟后到达B点,测得油井P在南偏东30°,然后,海轮改为东偏北60°的航向再航行80分钟到达C点,请你计算出P,C

如图,某海轮以每小时30海里的速度航行,在A点测得海面上油井P在南偏东60°,向北航行40分钟后到达B点,测得油井P在南偏东30°,然后,海轮改为东偏北60°的航向再航行80分钟到达C点,请你计算出P,C
如图,某海轮以每小时30海里的速度航行,在A点测得海面上油井P在南偏东60°,向北航行40分钟后到达B点,测得油井P在南偏东30°,然后,海轮改为东偏北60°的航向再航行80分钟到达C点,请你计算出P,C间的距离．

如图,某海轮以每小时30海里的速度航行,在A点测得海面上油井P在南偏东60°,向北航行40分钟后到达B点,测得油井P在南偏东30°,然后,海轮改为东偏北60°的航向再航行80分钟到达C点,请你计算出P,C
在△ABP中  AB=30*80/60=20（海里）
    ∠APB=30° ∠BAP=120°
        AB/sin30°=BD/sin120°   BP=20√3（海里）
    在△BCP中 BC=30*80/60=40（海里）
    ∠PBC=180°-30°-60°=90°
       PC=√（BC^2+BP^2）=√｛40^2+（20√3）^2｝=20√7（海里）

图？？？

BA=30X2/3=20(海里） BC=30X4/3=40(海里） 角BAP=180°—60°=120° 因为 角APB=角ABP=30° 所以 BA=AP=20海里 所以 20/1/2=BP/2/根号二 所以 BP=二十倍的根号三 又因为 角CBP=180°—60°—30°=90° 所以 在直角三角形BCP中 CP=根号下BC的方+BP的方=二十倍的根号七

The video window displays is their discrete 27-year son and daughter, Wang edge, granddaughter of the screen. Happy family at his son's smile, the joy of Chinese New Year reunion scene back home once ...

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The video window displays is their discrete 27-year son and daughter, Wang edge, granddaughter of the screen. Happy family at his son's smile, the joy of Chinese New Year reunion scene back home once again surfaced.
27 years ago

out to see the 5-year-old son made no television back

sixtieth year of Duqiong Sheng Wang Qihao and his wife have a daughter and a son, was born September 1976, the second son of King blade small smart, lively.
1982 年 3 月 11 evening, 5-year-old Wang edge they had dinner together with your sister to the old government compound in Nanba watching TV. Around 9:00 pm, said his brother's daughter home alone their first home, but does not see the edge of the king of the couple anxious to go home, and quickly started looking for friends and family separately, and in a timely manner to the area where the police station.
original, naughty king blade will advance to the middle of watching TV to go home alone, when he was just out of the government compound, met a bike lanky acquaintances, who graciously hold him into the rear frame of the basket, said to send him home. Lanky bicycle pedal too fast,Chaussures Louboutin Pas Cher, eyes to see the house edge in front of the king, refused to slow down to stop. Wang edge feeling some bad, suddenly anxious cry and kick. Unexpectedly, lanky hand toward the back edge face touched the king, so I do not know what trick, Wang edge immediately fainted ... ...

until the next morning, still not seen his wife Wang Wang Qihao edge trace.
years, as long as a child and get relevant clues, no matter the distance, Wang Qihao couple will leave immediately to catch the last search. The couple to find the child and toured around in Sichuan, still refuses to give up hope. Finally, Wang Qihao thought of missing children through the network, so, he nearly Nail quietly bought the computer, started to learn typing,Christian Louboutin pas cher, online.
Olympic Games, made a missing person

Year of the Ox Chinese New Year her son reunion

the eve of the Olympics last year, Wang Qihao relatives working in Guangzhou to Beijing to watch the occasion of the Olympic Games , produced specifically for the edge to find the king thousands of Soon, the news was Beijing,
New Year's half past one p.m., the temple is performing suburbs play Wangqi Hao, suddenly receive a The site is now tracing a master's situation, and Wang Qihao release of information to find the child is very similar,escarpins louboutin, suggesting that his time login While, the site, another volunteer
Wang Qihao talk with each other just after, another call came not wait to play: What is your name? Sure enough, the phone came out clear and certain other words: his wife excited like a child, then tears: Wang edge is removed, Liaocheng, Shandong Shenxian trafficked to the village in a mountain town name off people, they change their names to Wang blade did not mind after graduating from junior high school, he only who Beijing battles, working side to side quietly tracing ... ... On one occasion, the king edge sneak Internet access, and occasionally log on a website dedicated tracing enthusiastic volunteers, inspired by the patience, life experience of his own childhood memories slowly returned. New Year's Day afternoon, after the 19:30 two days, the king could not wait to get through the edge of his parents home phone. Early next morning, the king led the blade in the body of his wife and pregnant daughter joy left, after thousands of miles to drive home Jiangyou direction ... ... the first month of the fifth day at 5 pm, Wang Qihao to lead his wife and her son, who drove the starting , to the cotton wide high-speed toll Jiangyou North edge to meet the king and his wife and daughter.
27 years of their loved ones thirst, 27-year struggle to find ... ... and finally this morning in the Year of the Ox Chinese New Year dreams come true surprise! Chen Yuansong report

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