Evaluating $(sqrt{3}+i)^{2017} + (sqrt{3} - i)^{2017}$ [closed]












0












$begingroup$


I'm having a problem with following equation:



I'm applying $(a+b)^2$ and $(a-b)^2$, but am unable to get the correct answer.




$$(sqrt{3}+i)^{2017} + (sqrt{3} - i)^{2017}$$











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$endgroup$



closed as off-topic by José Carlos Santos, Namaste, Nosrati, Saad, user10354138 Dec 23 '18 at 19:39


This question appears to be off-topic. The users who voted to close gave this specific reason:


  • "This question is missing context or other details: Please provide additional context, which ideally explains why the question is relevant to you and our community. Some forms of context include: background and motivation, relevant definitions, source, possible strategies, your current progress, why the question is interesting or important, etc." – José Carlos Santos, Namaste, Nosrati, Saad, user10354138

If this question can be reworded to fit the rules in the help center, please edit the question.
















  • $begingroup$
    What have you gotten? (Please include the work you've done, even if you found it doesn't yield the correct answer.) Alternatively, you may cite the source of the question, and explain why it is of interest to you and or the general community.
    $endgroup$
    – Namaste
    Dec 23 '18 at 12:25






  • 1




    $begingroup$
    Yeah my bad, it's my first post :). What i tried was to apply the basic rules of $(a+b)^2$ and $(a-b)^2$. So what i got is $$(sqrt{3}+i)^{2017} + (sqrt{3} - i)^{2017} = 3^{1008}sqrt{3} + 3^{1008}sqrt{3}$$ I'm not sure it's the correct way to approach with complex numbers. I used $(a+b)^3$, but that didn't seem right also.
    $endgroup$
    – arts
    Dec 23 '18 at 12:35


















0












$begingroup$


I'm having a problem with following equation:



I'm applying $(a+b)^2$ and $(a-b)^2$, but am unable to get the correct answer.




$$(sqrt{3}+i)^{2017} + (sqrt{3} - i)^{2017}$$











share|cite|improve this question











$endgroup$



closed as off-topic by José Carlos Santos, Namaste, Nosrati, Saad, user10354138 Dec 23 '18 at 19:39


This question appears to be off-topic. The users who voted to close gave this specific reason:


  • "This question is missing context or other details: Please provide additional context, which ideally explains why the question is relevant to you and our community. Some forms of context include: background and motivation, relevant definitions, source, possible strategies, your current progress, why the question is interesting or important, etc." – José Carlos Santos, Namaste, Nosrati, Saad, user10354138

If this question can be reworded to fit the rules in the help center, please edit the question.
















  • $begingroup$
    What have you gotten? (Please include the work you've done, even if you found it doesn't yield the correct answer.) Alternatively, you may cite the source of the question, and explain why it is of interest to you and or the general community.
    $endgroup$
    – Namaste
    Dec 23 '18 at 12:25






  • 1




    $begingroup$
    Yeah my bad, it's my first post :). What i tried was to apply the basic rules of $(a+b)^2$ and $(a-b)^2$. So what i got is $$(sqrt{3}+i)^{2017} + (sqrt{3} - i)^{2017} = 3^{1008}sqrt{3} + 3^{1008}sqrt{3}$$ I'm not sure it's the correct way to approach with complex numbers. I used $(a+b)^3$, but that didn't seem right also.
    $endgroup$
    – arts
    Dec 23 '18 at 12:35
















0












0








0





$begingroup$


I'm having a problem with following equation:



I'm applying $(a+b)^2$ and $(a-b)^2$, but am unable to get the correct answer.




$$(sqrt{3}+i)^{2017} + (sqrt{3} - i)^{2017}$$











share|cite|improve this question











$endgroup$




I'm having a problem with following equation:



I'm applying $(a+b)^2$ and $(a-b)^2$, but am unable to get the correct answer.




$$(sqrt{3}+i)^{2017} + (sqrt{3} - i)^{2017}$$








calculus






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share|cite|improve this question













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share|cite|improve this question








edited Dec 23 '18 at 12:31









Blue

49.7k870158




49.7k870158










asked Dec 23 '18 at 12:13









artsarts

131




131




closed as off-topic by José Carlos Santos, Namaste, Nosrati, Saad, user10354138 Dec 23 '18 at 19:39


This question appears to be off-topic. The users who voted to close gave this specific reason:


  • "This question is missing context or other details: Please provide additional context, which ideally explains why the question is relevant to you and our community. Some forms of context include: background and motivation, relevant definitions, source, possible strategies, your current progress, why the question is interesting or important, etc." – José Carlos Santos, Namaste, Nosrati, Saad, user10354138

If this question can be reworded to fit the rules in the help center, please edit the question.







closed as off-topic by José Carlos Santos, Namaste, Nosrati, Saad, user10354138 Dec 23 '18 at 19:39


This question appears to be off-topic. The users who voted to close gave this specific reason:


  • "This question is missing context or other details: Please provide additional context, which ideally explains why the question is relevant to you and our community. Some forms of context include: background and motivation, relevant definitions, source, possible strategies, your current progress, why the question is interesting or important, etc." – José Carlos Santos, Namaste, Nosrati, Saad, user10354138

If this question can be reworded to fit the rules in the help center, please edit the question.












  • $begingroup$
    What have you gotten? (Please include the work you've done, even if you found it doesn't yield the correct answer.) Alternatively, you may cite the source of the question, and explain why it is of interest to you and or the general community.
    $endgroup$
    – Namaste
    Dec 23 '18 at 12:25






  • 1




    $begingroup$
    Yeah my bad, it's my first post :). What i tried was to apply the basic rules of $(a+b)^2$ and $(a-b)^2$. So what i got is $$(sqrt{3}+i)^{2017} + (sqrt{3} - i)^{2017} = 3^{1008}sqrt{3} + 3^{1008}sqrt{3}$$ I'm not sure it's the correct way to approach with complex numbers. I used $(a+b)^3$, but that didn't seem right also.
    $endgroup$
    – arts
    Dec 23 '18 at 12:35




















  • $begingroup$
    What have you gotten? (Please include the work you've done, even if you found it doesn't yield the correct answer.) Alternatively, you may cite the source of the question, and explain why it is of interest to you and or the general community.
    $endgroup$
    – Namaste
    Dec 23 '18 at 12:25






  • 1




    $begingroup$
    Yeah my bad, it's my first post :). What i tried was to apply the basic rules of $(a+b)^2$ and $(a-b)^2$. So what i got is $$(sqrt{3}+i)^{2017} + (sqrt{3} - i)^{2017} = 3^{1008}sqrt{3} + 3^{1008}sqrt{3}$$ I'm not sure it's the correct way to approach with complex numbers. I used $(a+b)^3$, but that didn't seem right also.
    $endgroup$
    – arts
    Dec 23 '18 at 12:35


















$begingroup$
What have you gotten? (Please include the work you've done, even if you found it doesn't yield the correct answer.) Alternatively, you may cite the source of the question, and explain why it is of interest to you and or the general community.
$endgroup$
– Namaste
Dec 23 '18 at 12:25




$begingroup$
What have you gotten? (Please include the work you've done, even if you found it doesn't yield the correct answer.) Alternatively, you may cite the source of the question, and explain why it is of interest to you and or the general community.
$endgroup$
– Namaste
Dec 23 '18 at 12:25




1




1




$begingroup$
Yeah my bad, it's my first post :). What i tried was to apply the basic rules of $(a+b)^2$ and $(a-b)^2$. So what i got is $$(sqrt{3}+i)^{2017} + (sqrt{3} - i)^{2017} = 3^{1008}sqrt{3} + 3^{1008}sqrt{3}$$ I'm not sure it's the correct way to approach with complex numbers. I used $(a+b)^3$, but that didn't seem right also.
$endgroup$
– arts
Dec 23 '18 at 12:35






$begingroup$
Yeah my bad, it's my first post :). What i tried was to apply the basic rules of $(a+b)^2$ and $(a-b)^2$. So what i got is $$(sqrt{3}+i)^{2017} + (sqrt{3} - i)^{2017} = 3^{1008}sqrt{3} + 3^{1008}sqrt{3}$$ I'm not sure it's the correct way to approach with complex numbers. I used $(a+b)^3$, but that didn't seem right also.
$endgroup$
– arts
Dec 23 '18 at 12:35












3 Answers
3






active

oldest

votes


















1












$begingroup$

I would use the Euler's formula. Say $z = sqrt{3} + i$.

So $tan(phi) = 1/sqrt{3}$

and $phi = pi/6$

and $r = |z|= sqrt{1^2 + sqrt{3}^2} = sqrt{4} = 2$

Meaning $z = 2 cdot e^{i pi/6}$, $overline z = 2 cdot e^{-i pi/6}$



$z^{2017} = 2^2017 cdot e^{i cdot 2017 cdotpi/6}$, $(overline z)^{2017} = 2^{2017} cdot e^{-i cdot 2017 cdotpi/6}$



Converting this back from $w= |w| cdot e^{i cdot psi}$ to the form $w = a + ib$
with $Re(w) = a = |w|cos(psi)$ and $Im(w) = b = |w|sin(psi)$



gives us
$$z^{2017} + (overline z)^{2017} = \
Re(z^{2017}) + Re((overline z)^{2017}) + icdot (Im(z^{2017}) + Im((overline z)^{2017})) = \
2^{2017} cos(2017 cdot pi / 6) + 2^{2017} cos(- 2017 cdot pi /6) + icdot (2^{2017} sin(2017 cdot pi / 6) + 2^{2017} sin(- 2017 cdot pi / 6)) = \
2^{2017} cos(2017 cdot pi / 6) + 2^{2017} cos(2017 cdot pi /6) + icdot (2^{2017} sin(2017 cdot pi / 6) - 2^{2017} sin(2017 cdot pi / 6)) = \
2^{2017} (2 cdot cos(2017 cdot pi /6)) = \
2^{2017} (2 cdot cos(pi /6)) = \
2^{2017} (2 frac{sqrt{3}}{2}) = \
2^{2017} sqrt{3}
$$






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$endgroup$





















    5












    $begingroup$

    Hint:



    It's probably easier to write $sqrt 3+i=re^{itheta}$ and $sqrt 3-i=re^{-itheta}$, by finding $r,theta$, and then use $$rcos(theta)=rfrac{e^{itheta}+e^{-itheta}}{2}$$






    share|cite|improve this answer











    $endgroup$





















      0












      $begingroup$

      Let $z=(sqrt 3 +i)^{2017}$, then $$z=2^{2017}e^{2017 ipi /6}$$



      $$Re(z)=2^{2017}cos {2017pi /6} =2^{2017} cos {pi/6}$$



      $z+bar z =2Re(z)=2^{2017}sqrt 3$






      share|cite|improve this answer











      $endgroup$













      • $begingroup$
        The exponent was supposed to be 2017 rather than 2007. In your case that means you get $Re(z) = 2^{2017} cos(2017 pi/6)$ which is $2^{2017} cos(pi /6) = 2^{2017} frac{sqrt{3}}{2}$
        $endgroup$
        – Coupeau
        Dec 23 '18 at 14:50










      • $begingroup$
        Thanks for the comment. I fixed my mistake
        $endgroup$
        – Mohammad Riazi-Kermani
        Dec 23 '18 at 16:02


















      3 Answers
      3






      active

      oldest

      votes








      3 Answers
      3






      active

      oldest

      votes









      active

      oldest

      votes






      active

      oldest

      votes









      1












      $begingroup$

      I would use the Euler's formula. Say $z = sqrt{3} + i$.

      So $tan(phi) = 1/sqrt{3}$

      and $phi = pi/6$

      and $r = |z|= sqrt{1^2 + sqrt{3}^2} = sqrt{4} = 2$

      Meaning $z = 2 cdot e^{i pi/6}$, $overline z = 2 cdot e^{-i pi/6}$



      $z^{2017} = 2^2017 cdot e^{i cdot 2017 cdotpi/6}$, $(overline z)^{2017} = 2^{2017} cdot e^{-i cdot 2017 cdotpi/6}$



      Converting this back from $w= |w| cdot e^{i cdot psi}$ to the form $w = a + ib$
      with $Re(w) = a = |w|cos(psi)$ and $Im(w) = b = |w|sin(psi)$



      gives us
      $$z^{2017} + (overline z)^{2017} = \
      Re(z^{2017}) + Re((overline z)^{2017}) + icdot (Im(z^{2017}) + Im((overline z)^{2017})) = \
      2^{2017} cos(2017 cdot pi / 6) + 2^{2017} cos(- 2017 cdot pi /6) + icdot (2^{2017} sin(2017 cdot pi / 6) + 2^{2017} sin(- 2017 cdot pi / 6)) = \
      2^{2017} cos(2017 cdot pi / 6) + 2^{2017} cos(2017 cdot pi /6) + icdot (2^{2017} sin(2017 cdot pi / 6) - 2^{2017} sin(2017 cdot pi / 6)) = \
      2^{2017} (2 cdot cos(2017 cdot pi /6)) = \
      2^{2017} (2 cdot cos(pi /6)) = \
      2^{2017} (2 frac{sqrt{3}}{2}) = \
      2^{2017} sqrt{3}
      $$






      share|cite|improve this answer











      $endgroup$


















        1












        $begingroup$

        I would use the Euler's formula. Say $z = sqrt{3} + i$.

        So $tan(phi) = 1/sqrt{3}$

        and $phi = pi/6$

        and $r = |z|= sqrt{1^2 + sqrt{3}^2} = sqrt{4} = 2$

        Meaning $z = 2 cdot e^{i pi/6}$, $overline z = 2 cdot e^{-i pi/6}$



        $z^{2017} = 2^2017 cdot e^{i cdot 2017 cdotpi/6}$, $(overline z)^{2017} = 2^{2017} cdot e^{-i cdot 2017 cdotpi/6}$



        Converting this back from $w= |w| cdot e^{i cdot psi}$ to the form $w = a + ib$
        with $Re(w) = a = |w|cos(psi)$ and $Im(w) = b = |w|sin(psi)$



        gives us
        $$z^{2017} + (overline z)^{2017} = \
        Re(z^{2017}) + Re((overline z)^{2017}) + icdot (Im(z^{2017}) + Im((overline z)^{2017})) = \
        2^{2017} cos(2017 cdot pi / 6) + 2^{2017} cos(- 2017 cdot pi /6) + icdot (2^{2017} sin(2017 cdot pi / 6) + 2^{2017} sin(- 2017 cdot pi / 6)) = \
        2^{2017} cos(2017 cdot pi / 6) + 2^{2017} cos(2017 cdot pi /6) + icdot (2^{2017} sin(2017 cdot pi / 6) - 2^{2017} sin(2017 cdot pi / 6)) = \
        2^{2017} (2 cdot cos(2017 cdot pi /6)) = \
        2^{2017} (2 cdot cos(pi /6)) = \
        2^{2017} (2 frac{sqrt{3}}{2}) = \
        2^{2017} sqrt{3}
        $$






        share|cite|improve this answer











        $endgroup$
















          1












          1








          1





          $begingroup$

          I would use the Euler's formula. Say $z = sqrt{3} + i$.

          So $tan(phi) = 1/sqrt{3}$

          and $phi = pi/6$

          and $r = |z|= sqrt{1^2 + sqrt{3}^2} = sqrt{4} = 2$

          Meaning $z = 2 cdot e^{i pi/6}$, $overline z = 2 cdot e^{-i pi/6}$



          $z^{2017} = 2^2017 cdot e^{i cdot 2017 cdotpi/6}$, $(overline z)^{2017} = 2^{2017} cdot e^{-i cdot 2017 cdotpi/6}$



          Converting this back from $w= |w| cdot e^{i cdot psi}$ to the form $w = a + ib$
          with $Re(w) = a = |w|cos(psi)$ and $Im(w) = b = |w|sin(psi)$



          gives us
          $$z^{2017} + (overline z)^{2017} = \
          Re(z^{2017}) + Re((overline z)^{2017}) + icdot (Im(z^{2017}) + Im((overline z)^{2017})) = \
          2^{2017} cos(2017 cdot pi / 6) + 2^{2017} cos(- 2017 cdot pi /6) + icdot (2^{2017} sin(2017 cdot pi / 6) + 2^{2017} sin(- 2017 cdot pi / 6)) = \
          2^{2017} cos(2017 cdot pi / 6) + 2^{2017} cos(2017 cdot pi /6) + icdot (2^{2017} sin(2017 cdot pi / 6) - 2^{2017} sin(2017 cdot pi / 6)) = \
          2^{2017} (2 cdot cos(2017 cdot pi /6)) = \
          2^{2017} (2 cdot cos(pi /6)) = \
          2^{2017} (2 frac{sqrt{3}}{2}) = \
          2^{2017} sqrt{3}
          $$






          share|cite|improve this answer











          $endgroup$



          I would use the Euler's formula. Say $z = sqrt{3} + i$.

          So $tan(phi) = 1/sqrt{3}$

          and $phi = pi/6$

          and $r = |z|= sqrt{1^2 + sqrt{3}^2} = sqrt{4} = 2$

          Meaning $z = 2 cdot e^{i pi/6}$, $overline z = 2 cdot e^{-i pi/6}$



          $z^{2017} = 2^2017 cdot e^{i cdot 2017 cdotpi/6}$, $(overline z)^{2017} = 2^{2017} cdot e^{-i cdot 2017 cdotpi/6}$



          Converting this back from $w= |w| cdot e^{i cdot psi}$ to the form $w = a + ib$
          with $Re(w) = a = |w|cos(psi)$ and $Im(w) = b = |w|sin(psi)$



          gives us
          $$z^{2017} + (overline z)^{2017} = \
          Re(z^{2017}) + Re((overline z)^{2017}) + icdot (Im(z^{2017}) + Im((overline z)^{2017})) = \
          2^{2017} cos(2017 cdot pi / 6) + 2^{2017} cos(- 2017 cdot pi /6) + icdot (2^{2017} sin(2017 cdot pi / 6) + 2^{2017} sin(- 2017 cdot pi / 6)) = \
          2^{2017} cos(2017 cdot pi / 6) + 2^{2017} cos(2017 cdot pi /6) + icdot (2^{2017} sin(2017 cdot pi / 6) - 2^{2017} sin(2017 cdot pi / 6)) = \
          2^{2017} (2 cdot cos(2017 cdot pi /6)) = \
          2^{2017} (2 cdot cos(pi /6)) = \
          2^{2017} (2 frac{sqrt{3}}{2}) = \
          2^{2017} sqrt{3}
          $$







          share|cite|improve this answer














          share|cite|improve this answer



          share|cite|improve this answer








          edited Dec 23 '18 at 13:49

























          answered Dec 23 '18 at 13:28









          CoupeauCoupeau

          1296




          1296























              5












              $begingroup$

              Hint:



              It's probably easier to write $sqrt 3+i=re^{itheta}$ and $sqrt 3-i=re^{-itheta}$, by finding $r,theta$, and then use $$rcos(theta)=rfrac{e^{itheta}+e^{-itheta}}{2}$$






              share|cite|improve this answer











              $endgroup$


















                5












                $begingroup$

                Hint:



                It's probably easier to write $sqrt 3+i=re^{itheta}$ and $sqrt 3-i=re^{-itheta}$, by finding $r,theta$, and then use $$rcos(theta)=rfrac{e^{itheta}+e^{-itheta}}{2}$$






                share|cite|improve this answer











                $endgroup$
















                  5












                  5








                  5





                  $begingroup$

                  Hint:



                  It's probably easier to write $sqrt 3+i=re^{itheta}$ and $sqrt 3-i=re^{-itheta}$, by finding $r,theta$, and then use $$rcos(theta)=rfrac{e^{itheta}+e^{-itheta}}{2}$$






                  share|cite|improve this answer











                  $endgroup$



                  Hint:



                  It's probably easier to write $sqrt 3+i=re^{itheta}$ and $sqrt 3-i=re^{-itheta}$, by finding $r,theta$, and then use $$rcos(theta)=rfrac{e^{itheta}+e^{-itheta}}{2}$$







                  share|cite|improve this answer














                  share|cite|improve this answer



                  share|cite|improve this answer








                  edited Dec 23 '18 at 12:20









                  mrtaurho

                  6,19771641




                  6,19771641










                  answered Dec 23 '18 at 12:19









                  cansomeonehelpmeoutcansomeonehelpmeout

                  7,3323935




                  7,3323935























                      0












                      $begingroup$

                      Let $z=(sqrt 3 +i)^{2017}$, then $$z=2^{2017}e^{2017 ipi /6}$$



                      $$Re(z)=2^{2017}cos {2017pi /6} =2^{2017} cos {pi/6}$$



                      $z+bar z =2Re(z)=2^{2017}sqrt 3$






                      share|cite|improve this answer











                      $endgroup$













                      • $begingroup$
                        The exponent was supposed to be 2017 rather than 2007. In your case that means you get $Re(z) = 2^{2017} cos(2017 pi/6)$ which is $2^{2017} cos(pi /6) = 2^{2017} frac{sqrt{3}}{2}$
                        $endgroup$
                        – Coupeau
                        Dec 23 '18 at 14:50










                      • $begingroup$
                        Thanks for the comment. I fixed my mistake
                        $endgroup$
                        – Mohammad Riazi-Kermani
                        Dec 23 '18 at 16:02
















                      0












                      $begingroup$

                      Let $z=(sqrt 3 +i)^{2017}$, then $$z=2^{2017}e^{2017 ipi /6}$$



                      $$Re(z)=2^{2017}cos {2017pi /6} =2^{2017} cos {pi/6}$$



                      $z+bar z =2Re(z)=2^{2017}sqrt 3$






                      share|cite|improve this answer











                      $endgroup$













                      • $begingroup$
                        The exponent was supposed to be 2017 rather than 2007. In your case that means you get $Re(z) = 2^{2017} cos(2017 pi/6)$ which is $2^{2017} cos(pi /6) = 2^{2017} frac{sqrt{3}}{2}$
                        $endgroup$
                        – Coupeau
                        Dec 23 '18 at 14:50










                      • $begingroup$
                        Thanks for the comment. I fixed my mistake
                        $endgroup$
                        – Mohammad Riazi-Kermani
                        Dec 23 '18 at 16:02














                      0












                      0








                      0





                      $begingroup$

                      Let $z=(sqrt 3 +i)^{2017}$, then $$z=2^{2017}e^{2017 ipi /6}$$



                      $$Re(z)=2^{2017}cos {2017pi /6} =2^{2017} cos {pi/6}$$



                      $z+bar z =2Re(z)=2^{2017}sqrt 3$






                      share|cite|improve this answer











                      $endgroup$



                      Let $z=(sqrt 3 +i)^{2017}$, then $$z=2^{2017}e^{2017 ipi /6}$$



                      $$Re(z)=2^{2017}cos {2017pi /6} =2^{2017} cos {pi/6}$$



                      $z+bar z =2Re(z)=2^{2017}sqrt 3$







                      share|cite|improve this answer














                      share|cite|improve this answer



                      share|cite|improve this answer








                      edited Dec 23 '18 at 16:08

























                      answered Dec 23 '18 at 13:27









                      Mohammad Riazi-KermaniMohammad Riazi-Kermani

                      42.2k42061




                      42.2k42061












                      • $begingroup$
                        The exponent was supposed to be 2017 rather than 2007. In your case that means you get $Re(z) = 2^{2017} cos(2017 pi/6)$ which is $2^{2017} cos(pi /6) = 2^{2017} frac{sqrt{3}}{2}$
                        $endgroup$
                        – Coupeau
                        Dec 23 '18 at 14:50










                      • $begingroup$
                        Thanks for the comment. I fixed my mistake
                        $endgroup$
                        – Mohammad Riazi-Kermani
                        Dec 23 '18 at 16:02


















                      • $begingroup$
                        The exponent was supposed to be 2017 rather than 2007. In your case that means you get $Re(z) = 2^{2017} cos(2017 pi/6)$ which is $2^{2017} cos(pi /6) = 2^{2017} frac{sqrt{3}}{2}$
                        $endgroup$
                        – Coupeau
                        Dec 23 '18 at 14:50










                      • $begingroup$
                        Thanks for the comment. I fixed my mistake
                        $endgroup$
                        – Mohammad Riazi-Kermani
                        Dec 23 '18 at 16:02
















                      $begingroup$
                      The exponent was supposed to be 2017 rather than 2007. In your case that means you get $Re(z) = 2^{2017} cos(2017 pi/6)$ which is $2^{2017} cos(pi /6) = 2^{2017} frac{sqrt{3}}{2}$
                      $endgroup$
                      – Coupeau
                      Dec 23 '18 at 14:50




                      $begingroup$
                      The exponent was supposed to be 2017 rather than 2007. In your case that means you get $Re(z) = 2^{2017} cos(2017 pi/6)$ which is $2^{2017} cos(pi /6) = 2^{2017} frac{sqrt{3}}{2}$
                      $endgroup$
                      – Coupeau
                      Dec 23 '18 at 14:50












                      $begingroup$
                      Thanks for the comment. I fixed my mistake
                      $endgroup$
                      – Mohammad Riazi-Kermani
                      Dec 23 '18 at 16:02




                      $begingroup$
                      Thanks for the comment. I fixed my mistake
                      $endgroup$
                      – Mohammad Riazi-Kermani
                      Dec 23 '18 at 16:02