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    Stuck on two questions, I'm looking for the full working out so I can work out for myself how it's done, I can do all the others but rearranging the ones divided by something I just can't do.....

    2d)  U n = 2n + 1/n - 3,  U n = 19/6 I know n = 9 from the book but I don't know how to rearrange it properly as I get all sorts

    2h)  Un = (-1)^n   n/n + 4, U n = 7/9 I know n = 14 from the book but same as above

    Thanks a lot

    This is how my working seems to be going....

    2d)  19/6 = 2n + 1/n - 3
    So I try to multiply by n - 3? then from there I get the answer - 21 over 4 obviously nothing like the answer 9
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    (Original post by popppyss)
    Stuck on two questions, I'm looking for the full working out so I can work out for myself how it's done, I can do all the others but rearranging the ones divided by something I just can't do.....

    2d)  U n = 2n + 1/n - 3,  U n = 19/6 I know n = 9 from the book but I don't know how to rearrange it properly as I get all sorts

    2h)  Un = (-1)^n   n/n + 4, U n = 7/9 I know n = 14 from the book but same as above

    Thanks a lot

    This is how my working seems to be going....

    2d)  19/6 = 2n + 1/n - 3
    So I try to multiply by n - 3? then from there I get the answer - 21 over 4 obviously nothing like the answer 9
    THere maybe some problem with your multiplying, because if you do it
    properly then you will get for n 63 over 7.
    2b )Ignore (-1)^n. It is only alternatively changing the sign of the terms
    but this not effect the value of terms.
    THen solve the equation to n.
 
 
 
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