Question

已知：點(diǎn)A（x₁，y₁）、B（x₂，y₂）、C（x₃，y₃）是函數(shù)y=﹣圖象上的三點(diǎn)，且x₁＜0＜x₂＜x₃則y₁、y₂、y₃的大小關(guān)系是（　�。�                                                                                        

A．y₁＜y₂＜y₃              B．y₂＜y₃＜y₁              C．y₃＜y₂＜y₁              D．無(wú)法確定

Answer 1

B【考點(diǎn)】反比例函數(shù)圖象上點(diǎn)的坐標(biāo)特征．                                           

【專題】壓軸題．                                                                              

【分析】對(duì)y=﹣，由x₁＜0＜x₂＜x₃知，A點(diǎn)位于第二象限，y₁最大，第四象限，y隨x增大而增大，y₂＜y₃，故y₂＜y₃＜y₁．                                                                                                   

【解答】解：∵y=﹣中k=﹣3＜0，                                                       

∴此函數(shù)的圖象在二、四象限，                                                              

∵點(diǎn)A（x₁，y₁）、B（x₂，y₂）、C（x₃，y₃）是函數(shù)y=﹣圖象上的三點(diǎn)，且x₁＜0＜x₂＜x₃，               

∴A點(diǎn)位于第二象限，y₁＞0，B、C兩點(diǎn)位于第四象限，                                

∵0＜x₂＜x₃，                                                                                    

∴y₂＜y₃，                                                                                         

∴y₂＜y₃＜y₁．                                                                                   

故選B．                                                                                            

【點(diǎn)評(píng)】本題考查了反比例函數(shù)圖象上點(diǎn)的坐標(biāo)特征，要學(xué)會(huì)比較圖象上點(diǎn)的坐標(biāo)．