Question

Calculati a=5×(-1)^m+3×(-1)^2m

Answer 1

Avem doua cazuri:
1) Consideram m - par si notam m= 2k

a=5*(-1)^2k+3*(-1)^(2*2k)
a= 5*1+3*1 = 8

2) Consideram m - impar si notam m= 2k+1

a=5*(-1)^(2k+1)+3*(-1)^(2*(2k+1))
a= 5*(-1)+3*1
a= - 5+3
a= - 2