给出下列命题:①若向量a·b=a·c,则向量b=c；②若向量AB·AC＞0,则△ABC为锐角三角形；给出下列命题:①若向量a·b=a·c,则向量b=c；②若向量AB·AC＞0,则△ABC为锐角三角形；③非零向量a和b满足|a|=|b

给出下列命题:①若向量a·b=a·c,则向量b=c；②若向量AB·AC＞0,则△ABC为锐角三角形；给出下列命题:①若向量a·b=a·c,则向量b=c；②若向量AB·AC＞0,则△ABC为锐角三角形；③非零向量a和b满足|a|=|b
给出下列命题:①若向量a·b=a·c,则向量b=c；②若向量AB·AC＞0,则△ABC为锐角三角形；
给出下列命题:
①若向量a·b=a·c,则向量b=c；
②若向量AB·AC＞0,则△ABC为锐角三角形；
③非零向量a和b满足|a|=|b|=|a+b|,则向量a与向量a-b的夹角为30°；
④设a0为单位向量,若向量a与向量a0平行,则向量a=|a|·a0；
其中正确命题的序号为

给出下列命题:①若向量a·b=a·c,则向量b=c；②若向量AB·AC＞0,则△ABC为锐角三角形；给出下列命题:①若向量a·b=a·c,则向量b=c；②若向量AB·AC＞0,则△ABC为锐角三角形；③非零向量a和b满足|a|=|b
无一正确.
①只能得出a与b-c垂直
②只能得出角A为锐角
③夹角为150度
④a与a0可能反向,这时 a=-|a|*a0

morning, Xiang Xiang's father holding him in the hospital to prepare 304 hospitalized,nike ken griffey jr shoes, Xiang Xiang waved goodbye to the reporters: Xiang Xiang in Beijing three days and final...

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morning, Xiang Xiang's father holding him in the hospital to prepare 304 hospitalized,nike ken griffey jr shoes, Xiang Xiang waved goodbye to the reporters: Xiang Xiang in Beijing three days and finally parents temporary relief.
morning, a law came late correspondent with Xiang Xiang's Liberation Army 304 Hospital,mbt running shoes, Burn and Plastic Surgery, the morning after a preliminary examination, the hospital decided to receive the 304 hospitalized Xiang Xiang, Burns and Plastic Surgery, ENT and anesthesia will be joint consultation, ultimately determine the treatment of Xiang Xiang.
Xiang Xiang is a Saturday to Beijing, Xiang Xiang Wei Yan Jun's mother told reporters later law,nike air max shoes, the child accident a month later, they visited Beijing Children's Hospital plastic surgery clinic, so the trip to Beijing They found a family hotel near the hospital stay, convenient medical treatment.
but yesterday's test results is not very optimistic. After detailed examination, Children's Hospital ENT doctor told Wangshou Wu,ken griffey jr shoes 2011, Xiang Xiang's not so good, now the trachea than the thin end of last year a lot of surgery that would seriously affect the child breathing. Do the same situation continues, there will be life-threatening.
Wangshou Wu Xiang Xiang surgery immediately think of to give,Web site evaluation America topped t mbt sport hig, no matter how much they have to save the child's life. But the doctor said:
to be just looking forward to Beijing for the cosmetic surgery Xiang Xiang, but did not think the bad news come again. Wang Shouwu choked with sobs,mbt outlet, now do not know how to do.
morning, a law came late correspondent with Xiang Xiang's Liberation Army 304 Hospital, Burn and Plastic Surgery, after a preliminary examination, the hospital decided to receive the 304 hospitalized Xiang Xiang, Burns and Plastic Surgery, ENT and anesthesia will be joint consultation, the final determine the treatment of Xiang Xiang.
304 Burns and Plastic Surgery Hospital of Shen Chuanan director,nike air max 24 7, said Xiang Xiang's facial plastic surgery treatments can be carried out at this stage, but the most important thing is to solve Xiang Xiang tracheal granulation blockage of breathing problems.
Shenzhu Ren said that for burn patients, this damage is a common aspiration, and surgical methods of treatment can be taken. Currently, 304 hospitals have decided to receive hospital treatment Xiang Xiang, Burn and Plastic Surgery will be combined ENT and anesthesia consultation,griffey shoes 2011, and ultimately determine the treatment of Xiang Xiang.
Xiang Xiang was born in 2005, lives in Shanxi Fenyang Mijiazhuangcun,griffeys, father Wangshou Wu, Wei Yan Jun Mom. In 2010,Lebron James Shoes women, Xiang Xiang as a fire and facial disfigurement. In order to cover scars, skin graft to help recover,Air Max Lebron VII, he must wear a tight caps, not living in the shadow of sunlight. Happy childhood innocence was being detained on this,onitsuka tiger, he becomes less than the small partners to avoid the
yesterday, Xiang Xiang's mother told reporters late law, Xiang Xiang before the accident, the family has no savings up. Xiang Xiang's brother was hospitalized with pneumonia in 2009, treatment for up to two years, the hospital several times under a critical condition notice, Wang Shouwu the farm before she saved all their savings all spent 60,000 yuan. Discharged from hospital after his brother, Wang Shouwu began work outside the home, hoping to make more money, and thus,mbt for women, annual family income of only 3,000. And Xiang Xiang the cost of medical treatment in Beijing for nearly 20 million, not including the cost of facial plastic surgery.

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第三个命题是正确的。
1.若a为零向量，则无论向量b，c情况如何，原等式都满足。
2.该不等式只能说明向量AB和向量AC的夹角是锐角，不能说明△ABC为锐角三角形。
4.向量|a|·a0是与向量a0方向一致的向量，而向量a有可能与向量a0方向相反。
正确的命题
3.根据条件，用向量加法的三角形法则就可看出：向量a，b与a+b正好构成一个等边三角形，而向量a，...

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第三个命题是正确的。
1.若a为零向量，则无论向量b，c情况如何，原等式都满足。
2.该不等式只能说明向量AB和向量AC的夹角是锐角，不能说明△ABC为锐角三角形。
4.向量|a|·a0是与向量a0方向一致的向量，而向量a有可能与向量a0方向相反。
正确的命题
3.根据条件，用向量加法的三角形法则就可看出：向量a，b与a+b正好构成一个等边三角形，而向量a，-b和a-b正好构成一个等腰钝角三角形，底角即为向量a与向量a-b的夹角，为30°。

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