1) 2.8х3.9= 10.92
2) 11.4х5.7=64.98
3)10.92+64.98=75.9
Ответ:75.9
Дима -х
мама-у
папа-z
х+у=40 у=40-х
х+z=42 z=42-х
х+у+z=74 х+(40-х)+(42-х)=74
х+40-х+42-х=74
82-х=74
х=8 - дима
мама = 40-8=32
папа = 42-8=34
1) (1/32)^(2x) >= sqrt(0.125)
0.5^(5*2x)>=0.5^(3/2)
10x <= 3/2
x<=3/20
x<=0.15
2) log(1/3, 5x-1) >=2
ОДЗ: 5x-1>0, x>0.2
log(1/3, 5x-1) >= log(1/3, 1/9)
5x-1 <= 1/9
x<=2/9
С учетом ОДЗ, 0.2 < x <= 2/9
5317+1498=6815
6365+7482=13847