If the printer should break down under g____, we would repair it at our expense.
已知双曲线x2a2-y2b2=1(a>0,b>0),过其右焦点且垂直于实轴的直线与双曲线交于M,N两点,O为坐标原点,若OM⊥ON,则双曲线的离心率为( )