Răspuns:
Explicație pas cu pas:
d)
2^2019 + 2^2020 + 2^2021 = 2^2019*(1 + 2 + 4) = 7*2^2019
32^404 = (2^5)^404 = 2^2020
0,5 = 5/10 = 1/2
7*2^2019/x = 2^2020/(1/2) = 2^2021
x = 7*2^2019/2^2021 = 7/4
e)
1 + 2 + 3 + ...+ 102 = 102*103/2 = 51*103
0,(3) = 3/9 = 1/3
(1/3)/103 = 1/3*103
x/51*103 = 1/3*103
x = 51*103/3*103 = 51/3 = 17
