A) 4
B) 3
C) 2
D) 1
Correct Answer: A
Solution :
Given, \[^{2n+1}{{P}_{n-1}}:2x-1\,{{P}_{n}}=3:5\] \[\Rightarrow \]\[\frac{(2n+1)!}{(n+2)!}\times \frac{(n-1)!}{(2n-1)!}=\frac{3}{5}\] \[\Rightarrow \]\[\frac{(2n+1)(2n)}{(n+2)(n+1)n}=\frac{3}{5}\] \[\Rightarrow \] \[10(2n+1)=3({{n}^{2}}+3n+2)\] \[\Rightarrow \]\[3{{n}^{2}}-11n-4=0\] \[\Rightarrow \]\[(3n+1)(n-4)=0\] \[\Rightarrow \]\[n=4\]You need to login to perform this action.
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