如题所述
78ä¹77åä¹4
=ï¼77+1)x77åä¹4
=77x77åä¹4+1x77åä¹4
=4å77åä¹4
17ä¹8åä¹3å8åä¹3
=8åä¹3xï¼17-1ï¼
=8åä¹3x16
=6