Question

16n!/(n-1)! >5n!/(n-2)!

Answer 1

16n!/(n-1)! >5n!/(n-2)!

16n>5(n-1)n

16n>5n^2-5n

5n^2-21n<0

5n(n-21/5)<0

 

 

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_______________ 0 ___________________ 21/5 ___________________

 

$nin(0;21/5)\\nin(0;4,2)$