Question

Ex 33
Dau coroana, repede!!

Answer 1

a)

[2^(n+3) -2^(n+2) -2^(n+1) -2^n -2]/30 <1

[2^(n+3) -2^(n+2) -2^(n+1) -2^n -2] <30

Factor comun 2^n

(2^n)[(8-4-2-1]-2<30

2^n <32

2^n <2^5

n<5

b)
[2^(n+3) -2^(n+2) -2^(n+1) -2^n -2]/30 =1

Idem: n=5

c)
[2^(n+3) -2^(n+2) -2^(n+1) -2^n -2]/30 >1

Idem: n>5