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Statement-1 The term indepandent of x in...

Statement-1 The term indepandent of x in the
expansion of ` (x^(2) + (1)/(x^(2)) + 2) ^(25) " is " ""^(50)C_(25)` .
Statement-2 In a binomial expansion middle term is indepandnet of x.

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To solve the problem, we need to analyze the statements provided and verify their correctness step by step. ### Step-by-Step Solution: 1. **Understanding the Expression**: We have the expression \((x^2 + \frac{1}{x^2} + 2)^{25}\). We need to find the term independent of \(x\) in this expansion. 2. **Rewriting the Expression**: We can rewrite the expression as: \[ (x^2 + 2 + \frac{1}{x^2})^{25} \] This can be treated as a trinomial expansion. 3. **Using the Multinomial Theorem**: The general term in the expansion of \((a + b + c)^n\) is given by: \[ \frac{n!}{p!q!r!} a^p b^q c^r \] where \(p + q + r = n\). Here, \(a = x^2\), \(b = 2\), and \(c = \frac{1}{x^2}\). 4. **Finding the General Term**: The general term \(T\) in the expansion can be expressed as: \[ T = \frac{25!}{p!q!r!} (x^2)^p (2)^q \left(\frac{1}{x^2}\right)^r \] Simplifying this gives: \[ T = \frac{25!}{p!q!r!} 2^q x^{2p - 2r} \] 5. **Condition for Independence from \(x\)**: For the term to be independent of \(x\), the exponent of \(x\) must be zero: \[ 2p - 2r = 0 \implies p = r \] 6. **Expressing \(p\), \(q\), and \(r\)**: Since \(p + q + r = 25\) and \(p = r\), we can substitute \(r\) with \(p\): \[ 2p + q = 25 \implies q = 25 - 2p \] 7. **Finding Valid Values for \(p\)**: Since \(q\) must be non-negative, we have: \[ 25 - 2p \geq 0 \implies p \leq 12.5 \] Thus, \(p\) can take integer values from \(0\) to \(12\). 8. **Finding the Term Independent of \(x\)**: The term independent of \(x\) occurs when \(p = 12\) (the maximum integer value): \[ q = 25 - 2(12) = 1 \quad \text{and} \quad r = 12 \] The term is: \[ T = \frac{25!}{12!1!12!} (2)^1 = \frac{25!}{12!12!} \cdot 2 \] This simplifies to: \[ T = 2 \cdot \binom{25}{12} \] 9. **Final Calculation**: The number of ways to choose \(12\) items from \(25\) is: \[ \binom{25}{12} = \binom{25}{13} = \frac{25!}{12!13!} \] Therefore, the term independent of \(x\) is: \[ 2 \cdot \binom{25}{12} = 2 \cdot \binom{50}{25} \] ### Conclusion: - **Statement 1**: The term independent of \(x\) in the expansion is indeed \( \binom{50}{25} \), hence **True**. - **Statement 2**: The middle term in a binomial expansion is not always independent of \(x\), hence **False**.
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