Log(3)x/log(3)x/27 ≥ 4/log(3)x + 8/(log^2(3) x - log(3) x^3)
ОДЗ x>0
log x ≠ 0 x≠1
log x/27 ≠ 0 x≠27
log^2(3)x - log(3)x^3≠ 0 x≠1 x≠3³=27
x∈(0 1) U (1 27) U (27 ∞)
log(3) x/27 = log(3)x - log(3) 27 = log(3)x - 3
log^2(3)x - log(3)x^3 = log^2(3) x - 3 log(3) x = log(3)x (log(3) x - 3)
log(3)x=t
t/(t-3) ≥ 4/t + 8/t(t-3)
(t² - 4(t-3) - 8) /t(t-3) ≥ 0
(t² - 4t + 12 -8)/t(t-3) ≥ 0
(t-2)²/t(t-3) ≥ 0
++++++ 0 ------- {2} -------3 ++++++++
t∈(-∞ 0) U {2} U (3 +∞)
log(3) x< 0
x<1
log(3) x = 2
x=9
log(3)x>3
x>27
пересекаем с ОДЗ
x = (0 1) U {9} U (27 +∞)
(3/4+5/6) делить на(11/2-3/5)*1 8/19-(1-7/8)*4=254/216
1) 3/4+5/6=9/12+10/12=19/12
2)11/2-3/5=55/10-15/10=40/10=8/2=4/1=4
3)1-7/8=8/8-7/8=1/8
4)19/12:4/1=19/12:1/4=19/48
5)19/48*1 8/19=19/48*27/19=48/27
6)1/8*4=4/8
7)48/27-4/8=364/216-108/216=254/216
ПОМОЕМУ ТАК
