题目

如图所示，在 中， 在线段 上， ， ， ，则边 的长为（ ） A．B．C．D． 答案：D【分析】 利用余弦定理求得 ，由此求得 ，进而求得 ，利用正弦定理求得.【详解】 在三角形 中，由余弦定理得 ， 所以 ，由于 ， 所以.在三角形 中，由正弦定理得.故选： D【点睛】 本小题主要考查正弦定理、余弦定理解三角形，属于中档题 .Is there someone you hate? Well, maybe you don’t really hate them．But you get really angry every time you think of them．If you don’t let this anger go, it can turn into bitterness （痛苦）． Bitterness appears when we can’t forgive （原谅） someone who has hurt us or made us angry．Someone might say or do something that hurts us．But instead of controlling the anger, we keep it deep inside．Before long, a bitter feeling begins to grow．We may think we’re hurting that person by criticizing （指责） him or her often, but we’re really only hurting ourselves． Bitterness can not only lead to serious health problems such as heart disease, but also hurt our relationships with friends and family members．No one enjoys being around an angry person for very long． If you see bitterness in your life, here are some ways to deal with it． l    Accept it Instead of trying to deny your anger, make it clear to yourself and accept it．See your anger for what it is and quickly deal with it． l    Stop making excuses for it You may feel you have a right to be angry．You may think you’re right and the other person is wrong．You may even secretly enjoy making the other person look bad．But in the end, bitterness hurts you much more than the other person．The bitterness will hold you back, and the other person will go on with his or her life． l    Forgive and forget it You probably can’t completely put the anger out of your mind．But you can decide to forgive the other person．Forget it and move on．You’ll enjoy better health and peace of mind．  1．According to the passage, we might get angry when someone __________． A．holds us back        B．forgets us             C．doesn’t like us        D．does hurt us 2．Bitterness comes from __________． A．our health problems like heart disease B．the anger that lives deep inside our mind C．the person who says something that hurts us D．our relationships with friends and family members  3．The underlined word “deny” in the passage means “__________”． A．误解                    B．否认                  C．疏远                     D．减轻 4．The best way to deal with the bitterness is to __________． A．make the person who hurts us look bad B．hate the person who hurts us very often   C．accept that you are hurting the other person D．forgive the person who hurts us and forget it 5．What can we learn from the passage? A．We should enjoy someone who hurts us． B．We should pay more attention to our friends． C．The peace of mind is more important than the hurt itself． D．It’s better to let bitterness go along with the other person．