मराठी

Find the Middle Term in the Expansion Of: (I) ( 2 3 X − 3 2 X ) 20

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प्रश्न

Find the middle term in the expansion of: 

(i)  \[\left( \frac{2}{3}x - \frac{3}{2x} \right)^{20}\]

 

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उत्तर

(i) Here,
n = 20  (Even number)  
Therefore, the middle term is the \[\left( \frac{n}{2} + 1 \right)\] th term, i.e., the 11th term.

\[Now, \]
\[ T_{11} = T_{10 + 1} \]
\[ = ^{20}{}{C}_{10} \left( \frac{2}{3}x \right)^{20 - 10} \left( \frac{3}{2x} \right)^{10} \]
\[ = ^{20}{}{C}_{10} \frac{2^{10}}{3^{10}} \times \frac{3^{10}}{2^{10}} x^{10 - 10} \]
\[ =^{20}{}{C}_{10}\]

 

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पाठ 18: Binomial Theorem - Exercise 18.2 [पृष्ठ ३८]

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आर.डी. शर्मा Mathematics [English] Class 11
पाठ 18 Binomial Theorem
Exercise 18.2 | Q 13.1 | पृष्ठ ३८

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