Question 1127653
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1:  find the n-th of 3, -6, +9, -12, . . . 


    <U>ANSWER</U> :  {{{a[n]}}} = {{{(-1)^(n+1)*(3n)}}},  n= 1, 2, 3, 4, . . . 



        Notice that I  <U>edited</U>  your post by placing commas where they should be . . . 




2:  find the n-th term of -1, +1/2, -1/3,  1/4, . . . 


    <U>ANSWER</U> :  {{{a[n]}}} = {{{(-1)^n*(1/n)}}},  n= 1, 2, 3, 4, . . . 


        Notice that I  <U>edited</U>  your post by placing commas where they should be . . . 
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