Find the coefficient of x^2 in the expansion of (1-x+x^2)^n
tried so many times ....please help.
Binomial Expansion
2008-10-22 9:31 am
回答 (1)
2008-10-22 11:17 am
✔ 最佳答案
The answer is as follows:圖片參考：http://i277.photobucket.com/albums/kk75/uncle_michael/20081022_mat_1.jpg?t=1224616574
收錄日期: 2021-04-15 19:12:24
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https://hk.answers.yahoo.com/question/index?qid=20081022000051KK00150