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Let `m ,n in N and g c d ( 2, n)=1.` if `30((30),(0))+((30),(1))+....+2((30),(28))+1((30),(29))=n.2^m`
then n+m is equal to
( here ` ((n),(k)) =""^(n)C_K`)

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The correct Answer is:
To solve the problem, we need to evaluate the expression given and find the values of \( n \) and \( m \) such that \( n + m \) can be calculated. ### Step-by-step Solution: 1. **Understanding the Expression**: We are given the expression: \[ S = 30 \binom{30}{0} + 29 \binom{30}{1} + 28 \binom{30}{2} + \ldots + 2 \binom{30}{28} + 1 \binom{30}{29} \] This can be rewritten as: \[ S = \sum_{k=0}^{29} (30-k) \binom{30}{k} \] 2. **Using the Binomial Theorem**: The binomial theorem states that: \[ (x+y)^n = \sum_{k=0}^{n} \binom{n}{k} x^{n-k} y^k \] We can use this to find the sum by differentiating. 3. **Differentiating the Binomial Expansion**: Consider the expansion of \( (x + 1)^{30} \): \[ (x + 1)^{30} = \sum_{k=0}^{30} \binom{30}{k} x^{30-k} \] Differentiating both sides with respect to \( x \): \[ 30(x + 1)^{29} = \sum_{k=0}^{30} (30-k) \binom{30}{k} x^{30-k-1} \] 4. **Substituting \( x = 1 \)**: Now, substituting \( x = 1 \): \[ 30(1 + 1)^{29} = \sum_{k=0}^{30} (30-k) \binom{30}{k} \cdot 1^{30-k-1} \] This simplifies to: \[ 30 \cdot 2^{29} = S \] 5. **Setting Up the Equation**: We have found that: \[ S = 30 \cdot 2^{29} \] According to the problem, \( S = n \cdot 2^m \). 6. **Identifying \( n \) and \( m \)**: From the equation \( 30 \cdot 2^{29} = n \cdot 2^m \), we can equate: \[ n = 30 \quad \text{and} \quad m = 29 \] 7. **Checking the Condition**: We are given that \( \gcd(2, n) = 1 \). Since \( n = 30 \) is even, we need to adjust \( n \) to satisfy this condition. We can express \( 30 \) as: \[ 30 = 2 \cdot 15 \] Thus, we can rewrite \( S \) as: \[ S = 2 \cdot 15 \cdot 2^{29} = 15 \cdot 2^{30} \] Here, we can set: \[ n = 15 \quad \text{and} \quad m = 30 \] 8. **Final Calculation**: Now, we can find \( n + m \): \[ n + m = 15 + 30 = 45 \] ### Conclusion: The final result is: \[ \boxed{45} \]
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