Ответ:х=0.5
Пошаговое объяснение:arcsin((5x-1)/3)+2arccos((5x-1)/3)=5π/6
arccos((5x-1)/3)=π/2-arcsin((5x-1)/3), при условии -1≤(5x-1)/3≤1;
-3≤(5x-1)≤3; -2≤5x≤4;-0.4≤x≤0.8;
arcsin((5x-1)/3)+2*(π/2-arcsin((5x-1)/3))=5π/6
π-arcsin((5x-1)/3)=5π/6
arcsin((5x-1)/3)=π/6
(5x-1)/3=0.5
5x-1=1.5
5x=2.5
x=2.5/5
х=0.5∈ОДЗ.