题目

_____ that the world’s first university was established in Takshila in 700 BC.（  ） A. It believes        B. It is believed     C. They are believed   D. It is believed in   答案：B  下列说法不正确的是（ ）A．方程x2=x有一根为0B．方程x2﹣1=0的两根互为相反数C．方程（x﹣1）2﹣1=0的两根互为相反数D．方程x2﹣x+2=0无实数根