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999…9*999...9+1999...9均有n个9,.化简本式.

题目详情
999…9*999...9+1999...9
均有n个9,.化简本式.
▼优质解答
答案和解析
999...9*999...9+1999...9
=999...9*999...9+999...9+1000...0(n个0)
=999...9*(999...9+1)+1000...0
=999...9*1000...0+1000...0
=(999...9+1)*1000...0
=1000...0*1000...0
=1000...0(2n个0)