Find the limit of complex number











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I have $$Z_n = e^{-i({frac{pi}{2}+{frac{1}{2n}}})}$$
Therefore, as $n to infty$,
$$operatorname{lim}Z_n = e^{-i{frac{pi}{2}}}$$
But the answer on the book is $i.$










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    $dfrac1nto0$ so the answer is $-i$.
    – Nosrati
    Nov 15 at 5:39















up vote
1
down vote

favorite












I have $$Z_n = e^{-i({frac{pi}{2}+{frac{1}{2n}}})}$$
Therefore, as $n to infty$,
$$operatorname{lim}Z_n = e^{-i{frac{pi}{2}}}$$
But the answer on the book is $i.$










share|cite|improve this question


















  • 1




    $dfrac1nto0$ so the answer is $-i$.
    – Nosrati
    Nov 15 at 5:39













up vote
1
down vote

favorite









up vote
1
down vote

favorite











I have $$Z_n = e^{-i({frac{pi}{2}+{frac{1}{2n}}})}$$
Therefore, as $n to infty$,
$$operatorname{lim}Z_n = e^{-i{frac{pi}{2}}}$$
But the answer on the book is $i.$










share|cite|improve this question













I have $$Z_n = e^{-i({frac{pi}{2}+{frac{1}{2n}}})}$$
Therefore, as $n to infty$,
$$operatorname{lim}Z_n = e^{-i{frac{pi}{2}}}$$
But the answer on the book is $i.$







limits complex-numbers






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asked Nov 15 at 5:32









user3132457

546




546








  • 1




    $dfrac1nto0$ so the answer is $-i$.
    – Nosrati
    Nov 15 at 5:39














  • 1




    $dfrac1nto0$ so the answer is $-i$.
    – Nosrati
    Nov 15 at 5:39








1




1




$dfrac1nto0$ so the answer is $-i$.
– Nosrati
Nov 15 at 5:39




$dfrac1nto0$ so the answer is $-i$.
– Nosrati
Nov 15 at 5:39










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Note that $$e^{-ipi /2} = cos (-pi/2) -i sin(pi/2)=-i$$



Thus the book has a typo.






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    1 Answer
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    1 Answer
    1






    active

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    active

    oldest

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    up vote
    1
    down vote



    accepted










    Note that $$e^{-ipi /2} = cos (-pi/2) -i sin(pi/2)=-i$$



    Thus the book has a typo.






    share|cite|improve this answer

























      up vote
      1
      down vote



      accepted










      Note that $$e^{-ipi /2} = cos (-pi/2) -i sin(pi/2)=-i$$



      Thus the book has a typo.






      share|cite|improve this answer























        up vote
        1
        down vote



        accepted







        up vote
        1
        down vote



        accepted






        Note that $$e^{-ipi /2} = cos (-pi/2) -i sin(pi/2)=-i$$



        Thus the book has a typo.






        share|cite|improve this answer












        Note that $$e^{-ipi /2} = cos (-pi/2) -i sin(pi/2)=-i$$



        Thus the book has a typo.







        share|cite|improve this answer












        share|cite|improve this answer



        share|cite|improve this answer










        answered Nov 15 at 5:43









        Mohammad Riazi-Kermani

        39.8k41957




        39.8k41957






























             

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