> 数学 >
15+115+1115······+1111111115的简便计算(递等式计算)
人气:414 ℃ 时间:2020-09-11 07:57:13
解答
15+115+1115······+1111111115
= 10+5+110+5+1110+ 5······+1111111110+5
= 10+110 +1110 +······+1111111110 + 5×9
= 1234567890 + 5×9
= 1234567935
推荐
猜你喜欢
© 2024 79432.Com All Rights Reserved.
电脑版|手机版