Mathematical Induction Prove the Formula











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Given a positive number $a$ and a positive integer $k$. Let the sequence $x_n$ be given recurrently: $x_1 = a^{frac{1}{k}}$, $x_{n + 1} = frac{a}{x_n} ^ {frac{1}{k}}$. Prove that the general term formula has the form $x_n = a^{frac{1 - (- k) ^{- n}}{k + 1}}$










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    Given a positive number $a$ and a positive integer $k$. Let the sequence $x_n$ be given recurrently: $x_1 = a^{frac{1}{k}}$, $x_{n + 1} = frac{a}{x_n} ^ {frac{1}{k}}$. Prove that the general term formula has the form $x_n = a^{frac{1 - (- k) ^{- n}}{k + 1}}$










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      Given a positive number $a$ and a positive integer $k$. Let the sequence $x_n$ be given recurrently: $x_1 = a^{frac{1}{k}}$, $x_{n + 1} = frac{a}{x_n} ^ {frac{1}{k}}$. Prove that the general term formula has the form $x_n = a^{frac{1 - (- k) ^{- n}}{k + 1}}$










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      Given a positive number $a$ and a positive integer $k$. Let the sequence $x_n$ be given recurrently: $x_1 = a^{frac{1}{k}}$, $x_{n + 1} = frac{a}{x_n} ^ {frac{1}{k}}$. Prove that the general term formula has the form $x_n = a^{frac{1 - (- k) ^{- n}}{k + 1}}$







      induction






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      asked Nov 23 at 12:57









      sclerd

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          1. The formula is valid for $n=1$.

          2. Assuming it is valid for $n$, calculate
            $$x_{n+1}=left(frac a{x_n}right)^{1/k}=left(a^{1-frac{1-(-k)^n}{k+1}}right)^{1/k}=dots$$






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            1 Answer
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            active

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            up vote
            0
            down vote














            1. The formula is valid for $n=1$.

            2. Assuming it is valid for $n$, calculate
              $$x_{n+1}=left(frac a{x_n}right)^{1/k}=left(a^{1-frac{1-(-k)^n}{k+1}}right)^{1/k}=dots$$






            share|cite|improve this answer

























              up vote
              0
              down vote














              1. The formula is valid for $n=1$.

              2. Assuming it is valid for $n$, calculate
                $$x_{n+1}=left(frac a{x_n}right)^{1/k}=left(a^{1-frac{1-(-k)^n}{k+1}}right)^{1/k}=dots$$






              share|cite|improve this answer























                up vote
                0
                down vote










                up vote
                0
                down vote










                1. The formula is valid for $n=1$.

                2. Assuming it is valid for $n$, calculate
                  $$x_{n+1}=left(frac a{x_n}right)^{1/k}=left(a^{1-frac{1-(-k)^n}{k+1}}right)^{1/k}=dots$$






                share|cite|improve this answer













                1. The formula is valid for $n=1$.

                2. Assuming it is valid for $n$, calculate
                  $$x_{n+1}=left(frac a{x_n}right)^{1/k}=left(a^{1-frac{1-(-k)^n}{k+1}}right)^{1/k}=dots$$







                share|cite|improve this answer












                share|cite|improve this answer



                share|cite|improve this answer










                answered Nov 23 at 15:41









                Berci

                59.4k23672




                59.4k23672






























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