1/2 = 3/6
1/6 = 1/6
2/3 = 4/6
Z=(12+5i)/(2+3i)^2 = (12+5i)/(4 + 12i +9i^2) = (12+5i)/(4 + 12i -9) = (12+5i)/(12i -5) =
домножим всю дробь на (-12i - 5)
<span>=(12+5i)*(-12i -5)/(12i -5)*(-12i - 5)] = (-144i - 60 - 60i^2 -25i)/(144 +25) = (-144i - 25i)/169 = </span>
<span>= -169i/169 = -i</span>
C*30=90
C=90:30
C=3
d:40=2
d=2*40
d=80
75:X=1
X=75:1
X=75