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Ch. 8 - Sequences, Induction, and Probability
Blitzer - College Algebra 8th Edition
Blitzer8th EditionCollege AlgebraISBN: 9780136970514Non è quello che usi tu?Cambia libro di testo
Capitolo 9, Problema 55

Find the middle term in the expansion of (3/x + x/3)10

Guida verificata passo dopo passo
1
Identify the binomial expression and the exponent: the expression is \(\left( \frac{3}{x} + \frac{x}{3} \right)^{10}\), where \(n = 10\).
Recall the general term in the binomial expansion of \((a + b)^n\) is given by \(T_{k+1} = \binom{n}{k} a^{n-k} b^k\), where \(k\) ranges from 0 to \(n\).
Determine the middle term: since \(n = 10\) is even, the middle term is the \(\left( \frac{n}{2} + 1 \right)\)-th term, which is the 6th term (where \(k = 5\)).
Substitute \(a = \frac{3}{x}\), \(b = \frac{x}{3}\), \(n = 10\), and \(k = 5\) into the general term formula: \(T_6 = \binom{10}{5} \left( \frac{3}{x} \right)^{10-5} \left( \frac{x}{3} \right)^5\).
Simplify the powers and combine like terms carefully, paying attention to the exponents of \(x\) and the constants, to express the middle term in its simplest form.

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