Question 908676
Please help me solve this:
 1. In how many ways can 5 people be arranged on a bench?::: 5! = 120
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around a circular table?:: 4! = 24
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 2. If two of them insist on sitting next to each other, how many arrangements are possible?
Arrangements of the special 2:: 2 ways
Arrangements of the 5 where 2 act as a unit: 4!
Ans 4!*2 = 24*2 = 48 arrangements
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 Give two sets A, B and an application f:A -> B such that:
Use Google to see examples.
Search for "bijective function".

 a) f is bijective,
 b) is injective, but not surjective,
 c) f is surjective, but not injective,
 d) f is neither injective nor surjective.
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Cheers,
Stan H.