11/12+5/6= 11/12+10/12=21/12-3/4=21/12-9/12=12/12=1
300т/x=13.5%/100% => 300т*100=13.5x
30000т=13.5x
x=30000т/13.5
x~222т
<span>cos x = 1/2
x = ± arccos(1/2) + 2pik
x = ± pi/3 + 2pik, k ∈Z
</span>9!/2!*7! = (7! * 8 * 9 ) / (2 * 7!) = (8*9)/2 = 72/2 = 36
log 1/3 (4x+5) = - 1
log 1/3 (4x+5) = log 1/3 (3)
ОДЗ
4x + 5>0
4x > - 5
x > - 1,25
4x +5 = 3
4x = 3 - 5
4x = - 2
x = - 1/2 = - 0,5 ==> удовлет ОДЗ
ОТВЕТ: - 0,5
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