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(-1)^2 + (-1)^3 + ...+ (-1)^100 = ?​

Răspuns :

(-1)² + (-1)³ + ...+ (-1)¹⁰⁰ =

1-1+1-1+...+1=

0+0+0+...+1=

=1

Numerele impare la o putere para iasa un numar par.

Numerele impare la o putere para iasa un numar impar.

Succes!

[tex]\displaystyle (-1)^2+(-1)^3+(-1)^4+(-1)^5+...+(-1)^{100} = \\\\ = (-1)^2+(-1)^3+(-1)^4+(-1)^5+...+\\ +(-1)^{100} +(-1)^{101}+1=\\ \\ =\sum\limits_{k=1}^{50}\Big[(-1)^{2k}+(-1)^{2k+1}\Big]+1 = \\ \\ =\sum\limits_{k=1}^{50}\big(1-1\big)+1 = \\ \\ = \sum\limits_{k=1}^{50 }0 +1 = \\ \\ =0 +1 = \\ \\=1[/tex]