Which expression represents the sixth term in the binomial expansion of (5y + 3)10?
Answer
A
10C5(5y)5(3)5
B
10C6(5y)4(3)6
C
510C5(y)5(3)5
D
510C6(y)4(3)6
Explanation
In the expansion of (a + b)^10, the term in position r + 1 is 10Cr · a^(10−r) · b^r. For the sixth term, r = 5, so it is 10C5(5y)^5(3)^5. This matches choice A.
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