The (r + 1)th term in the expansion of (a + x)^n is:
Correct answer: D. (n choose r) a^(n-r+1) x^r+1
- A. (n choose r+1) a^(n-r-1) x^r
- B. (n choose r) a^(n-r) x^r
- C. (n choose r-1) a^(n-r+1) x^r+1
- D. (n choose r) a^(n-r+1) x^r+1
Explanation
The general term of the binomial expansion (a + x)^n is given by the formula:(n choose r) a^(n-r) x^rWhere:n is the exponent of the binomial expressionr is the index of the term in the expansion(n choose r) represents the binomial coefficient, which is the number of ways to choose r objects from n objects.The (r + 1)th term in the expansion is the term with index r + 1. To get this term, we need to replace r with r + 1 in the general term formula:(n choose r+1) a^(n-(r+1)) x^(r+1)
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