Explicație pas cu pas:
E = 3×(-1)^(n+2) + 4×(-1)^(2n+1) - 5
n impar
[tex]E = 3 \times (-1)^{n+2} + 4 \times (-1)^{2n+1} - 5 = 3 \times (-1) + 4 \times (-1) - 5 = - 3 - 4 - 5 = \bf - 12[/tex]
n par
[tex]E = 3 \times (-1)^{n+2} + 4 \times (-1)^{2n+1} - 5 = 3 \times ( + 1) + 4 \times (-1) - 5 = 3 - 4 - 5 = 3 - 9 = \bf - 6[/tex]