Question

△ABC中，AB=8，BC=4，則△ABC中最小的角是（　　）                            

A．∠A                        B．∠B                         C．∠C                        D．無法判斷

Answer 1

A【考點】三角形三邊關系．                                                                   

【專題】應用題．                                                                              

【分析】根據：兩邊之差＜三角形一條邊＜兩邊之和，得出第三條邊，再根據邊和角的對應關系，即可得出結果．                                                                             

【解答】解：根據兩邊之差＜三角形一條邊＜兩邊之和，                               

∴4＜第三邊＜12，                                                                            

故BC邊最短，                                                                                  

∴∠A最小，                                                                                     

故選A．                                                                                            

【點評】本題主要考查了三角形的三邊關系兩邊之差＜三角形一條邊＜兩邊之和，同時考查了邊和角的對應關系，難度適中．