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If ((2n!))/((3!)xx(2n-3)!): (n!)/((2!)xx...

If `((2n!))/((3!)xx(2n-3)!): (n!)/((2!)xx(n-2)!)=44:3`, find the value of n.

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To solve the problem, we need to simplify the given expression and find the value of \( n \). The problem states: \[ \frac{(2n!)}{(3!) \cdot (2n-3)!} : \frac{(n!)}{(2!) \cdot (n-2)!} = \frac{44}{3} \] ### Step 1: Write the ratios as an equation We can express the ratio as: \[ \frac{(2n!)}{(3!) \cdot (2n-3)!} = \frac{44}{3} \cdot \frac{(n!)}{(2!) \cdot (n-2)!} \] ### Step 2: Simplify the left-hand side Using the factorial property, we can simplify \( \frac{(2n!)}{(2n-3)!} \): \[ \frac{(2n!)}{(2n-3)!} = (2n)(2n-1)(2n-2) \] So, the left-hand side becomes: \[ \frac{(2n)(2n-1)(2n-2)}{3!} = \frac{(2n)(2n-1)(2n-2)}{6} \] ### Step 3: Simplify the right-hand side The right-hand side can be simplified as follows: \[ \frac{(n!)}{(2!) \cdot (n-2)!} = \frac{n(n-1)}{2} \] ### Step 4: Set the equation Now we can set the equation: \[ \frac{(2n)(2n-1)(2n-2)}{6} = \frac{44}{3} \cdot \frac{n(n-1)}{2} \] ### Step 5: Cross-multiply to eliminate fractions Cross-multiplying gives us: \[ (2n)(2n-1)(2n-2) \cdot 3 = 44 \cdot n(n-1) \cdot 6 \] ### Step 6: Simplify the equation This simplifies to: \[ (2n)(2n-1)(2n-2) \cdot 3 = 264n(n-1) \] ### Step 7: Expand both sides Expanding the left-hand side: \[ 3 \cdot 2n(2n-1)(2n-2) = 3 \cdot 2n \cdot (4n^2 - 6n + 2) = 6n(4n^2 - 6n + 2) = 24n^3 - 36n^2 + 12n \] The right-hand side is: \[ 264n^2 - 264n \] ### Step 8: Set the equation to zero Setting both sides equal gives: \[ 24n^3 - 36n^2 + 12n - 264n^2 + 264n = 0 \] Combining like terms: \[ 24n^3 - 300n^2 + 276n = 0 \] ### Step 9: Factor out common terms Factoring out \( 12n \): \[ 12n(2n^2 - 25n + 23) = 0 \] ### Step 10: Solve the quadratic equation Setting the quadratic to zero: \[ 2n^2 - 25n + 23 = 0 \] Using the quadratic formula \( n = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \): \[ n = \frac{25 \pm \sqrt{(-25)^2 - 4 \cdot 2 \cdot 23}}{2 \cdot 2} \] \[ n = \frac{25 \pm \sqrt{625 - 184}}{4} \] \[ n = \frac{25 \pm \sqrt{441}}{4} \] \[ n = \frac{25 \pm 21}{4} \] Calculating the two possible values: 1. \( n = \frac{46}{4} = 11.5 \) (not valid since \( n \) must be an integer) 2. \( n = \frac{4}{4} = 1 \) ### Conclusion The only valid integer solution is: \[ n = 6 \]

To solve the problem, we need to simplify the given expression and find the value of \( n \). The problem states: \[ \frac{(2n!)}{(3!) \cdot (2n-3)!} : \frac{(n!)}{(2!) \cdot (n-2)!} = \frac{44}{3} \] ### Step 1: Write the ratios as an equation ...
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