A) \[-4\]
B) \[-8\]
C) 6
D) 10
Correct Answer: A
Solution :
Put \[1+x=y,\] we get \[1+{{(y-1)}^{4}}+{{(y-1)}^{5}}=\sum\limits_{i=0}^{5}{{{a}_{i}}{{y}^{i}}}\] \[\therefore \] Equate coefficient of \[{{y}^{2}}\] on both sides, we get \[{{a}_{2}}{{=}^{4}}{{C}_{2}}{{-}^{5}}{{C}_{3}}=6-10\,=-4\]You need to login to perform this action.
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