問題詳情

(f) The coefficient of x2y in (x + 2y- 5)4 is
(A) 10
(B)-10
(C) 24
(D)-24
(E) None of above.

參考答案

答案：[無官方正解]
難度：適中0.5
統計：A(0),B(0),C(0),D(0),E(0)