在△ABC中,∠ACB=90度,CD⊥AB AC=4 BD=7,sinA等于多少,tanB等于多少

在△ABC中,∠ACB=90度,CD⊥AB AC=4 BD=7,sinA等于多少,tanB等于多少
在△ABC中,∠ACB=90度,CD⊥AB AC=4 BD=7,sinA等于多少,tanB等于多少

在△ABC中,∠ACB=90度,CD⊥AB AC=4 BD=7,sinA等于多少,tanB等于多少
根据摄影定理（初中的话要拿相似证）：AC^2=AB*AD.设AD为x,则有方程x*(x+7)=16,解得x=（根号下113-7）/2.剩下的用勾股定理把边导一导就好了
P.S:你的数没有抄错吗?这结果有点太复杂了

漏掉了条件 无法计算

射影定理，学过了吧，求出AD，问题就解决了，如果BD=6，则很容易，是不抄错了

Soup, nutritious, and relatively easy to digest, the United States to a survey conducted by nutritionists indicate that more than 60,000 people to receive nutrition survey, those well-nourished people...

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Soup, nutritious, and relatively easy to digest, the United States to a survey conducted by nutritionists indicate that more than 60,000 people to receive nutrition survey, those well-nourished people, it is often the person soup. But if we do not find time to drink, you eat more,but better fat.
Many people think that soup is a very simple matter, does not know that the only scientifically soup can both absorb nutrients, but also to avoid the accumulation of fat. In this regard, what we need to pay attention to it?
Before drinking, to drink after a meal differences: the time is about soup, the saying goes, "eating soup, slim and healthy; meal soup, eat more, better fat", which is a grain of truth. Soup before eating the first few drinks to mouth, esophagus lubrication you can prevent dry hard foods stimulate the digestive tract mucosa and is conducive to food dilution and mixing, to promote digestion and absorption. The most important thing is the food before eating stomach soup can fully close to the stomach wall,rolex watches, and enhance a sense of satiety,uggs outlet, thereby inhibiting feeding center, reducing people's appetite.
Studies have shown that: a bowl of soup in the meal drink, you can make 100-190 kcal less heat absorption. In contrast, after a meal is a soup eat to cause adverse health effects. On the one hand, have to eat rice and soup and then easily lead to excess nutrients,omega watches, resulting in obesity; In addition, the soup will be the last drink that has been well-mixed chyme digestive juice diluted the impact of food digestion and absorption.
Not easy to gain weight at soup: early, middle and late meal which is more suitable for this soup? Some experts pointed out that the "soup lunch to absorb the heat at least" and therefore, in order to prevent gain weight, may choose soup at noon. The dinner was not too much to drink soup, rapid absorption of nutrients or the accumulation in the body, it is easy to lead to weight gain.
The best choice to do low-fat food soup: soup to prevent gain weight, should be minimal use of high-fat, high-calorie food so soup, such as the old hen, such as The Fat Duck. That is, they do use soup, stew the best in the process of write-out of excess fat. And lean meat, fish, shrimp,cartier watches, chicken or duck skin, rabbit meat, white gourd, sponge gourd, radish, konnyaku, tomatoes,mbt shoe, seaweed, kelp, green bean sprouts, are very good low-fat soup, it may more Some selected.
Soup more slowly the more fat is not easy: The United States nutritionist pointed out that if the extension of time to eat, you can fully enjoy the taste of food and feed has been generated ahead of time feeling. The same is true of soup. Soup will slow digestion and absorption of food set aside sufficient time to fill the time felt that the time to eat right; and fast soup, and you realize that the full might of the food intake has exceeded the required the amount.

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