#1
2 3/4=11/4
обратная-4/11
11/4:4/11=11/4*11/4=121/16
#2
(3,5+1,2b)+(-6a+4,8b)=3,5+1,2b-6a+4,8b=
6b-6a+3,5
Ctg п/6=√3
log3 √3=log3 3^1/2=1/2
1) Z = 8 8\11 - 3 9\11 = 7 19\11 - 3 9\11 = 4 10\11
2) Y = 4\5 + 4 3\5 = 4 7\5 = 5 2\5 = 5.4
3) X - 2 17\27 = 8 16\27 - 8 5\27
X - 2 17\27 = 11\27
X = 11\27 + 2 17\27
X = 2 28\27
X = 3 1\27