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Math Help - 1-1 and onto

  1. #1
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    1-1 and onto

    can we find such a function which obeys the given rules;
    1.)it is defined on integer to integer,and 1-1 and onto,
    2.)f(1)=-5,f(7)=17,
    3.)and for all n>5,f(2n)=2n.
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  2. #2
    Grand Panjandrum
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    Quote Originally Posted by sah_mat View Post
    can we find such a function which obeys the given rules;
    1.)it is defined on integer to integer,and 1-1 and onto,
    2.)f(1)=-5,f(7)=17,
    3.)and for all n>5,f(2n)=2n.

     <br />
f(n) = \begin{cases} -5, & n =1<br />
\\ 1, & n =-5<br />
\\ 17, & n=7<br />
\\ 7,&n=17<br />
\\ n,& {\rm{otherwise}} <br /> <br />
\end{cases}<br />
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