Simplify the following expression and express your answer in factorial signs(!) 8×8!+7×7!+6×6!+5×5!+4×4!+3×3!+2×2!+1×1!?
回答 (2)
2016-02-27 3:41 pm
✔ 最佳答案
8×8! + 7×7! + 6×6! + 5×5! + 4×4! + 3×3! + 2×2! + 1×1!= (9-1)8! + (8-1)7! + (6-1)5! + (5-1)4! + (4-1)3! + (3-1)2! + (2-1)1!
= 9! - 8! + 8! - 7! + 6! - 5! + 5! - 4! + 4! - 3! + 3! - 2! + 2! - 1!
= 9! - 1
2016-02-28 1:55 am
8×8! + 7×7! + 6×6! + 5×5! + 4×4! + 3×3! + 2×2! + 1×1!
= (9-1)8! + (8-1)7! + (6-1)5! + (5-1)4! + (4-1)3! + (3-1)2! + (2-1)1!
= 9! - 8! + 8! - 7! + 6! - 5! + 5! - 4! + 4! - 3! + 3! - 2! + 2! - 1!
= 9! - 1
=362879
= (9-1)8! + (8-1)7! + (6-1)5! + (5-1)4! + (4-1)3! + (3-1)2! + (2-1)1!
= 9! - 8! + 8! - 7! + 6! - 5! + 5! - 4! + 4! - 3! + 3! - 2! + 2! - 1!
= 9! - 1
=362879
收錄日期: 2021-04-18 14:31:20
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