<span>а) 2 3/8:х=7,125:10 (произв крайних = произв средних):
2 3\8*10 = 7,125*х
190\8 = 7,125х
х = 190\8*1000\7125 = 190\8*8\57
х = 10\3
х = 3 1\3
б) 1,75:3,25=15:х
х = 27 6\7
х+1\4х = 16
1 14х = 16
5\4х = 16
х = 16*4\5
х = 64\5
х = 12,8
(12,8+3,2 = 16)</span>
A) i²³ = i²² * i = (i²)¹¹ * i = (-1)¹¹ * i = -i
b) i⁷ + i²¹ + i³¹ = i⁶ * i + i²⁰ * i + i³⁰ * i =
= i * ( (i²)³ + (i²)¹⁰ + (i²)¹⁵ ) = i * (-1 + 1 - 1) = -i
А)<span>3:х=7:1/3
1/3*3 = 7x
1 = 7x
x = 1/7
б)</span><span>3,6:0,12=6:х
3,6x = 0,12*6
3,6x = 0,72
x = 0,2</span>