2sin(2x/3) ≤ -1
sin(2x/3) ≤ -1/2
4π/3 + 2πn ≤ 2x/3 ≤ 5π/3 + 2πn, n∈Z |*3/2
2π+2πn ≤ x ≤ 2,5π+2πn, n∈Z
[2π+2πn ; 2,5π+2πn] , n∈Z
2cos(3π-x/4)+3sin(π/2-x/4)<0
-2cos x/4 + 3cos x/4 <0
cos x/4 <0
π/2 + 2πn < x/4 < 3π/2 + 2πn, n∈Z |*4
2π+4πn < x < 3π + 4πn, n∈Z
(2π+4πn; 3π + 4πn), n∈Z
100-5=95\% - от стоимости заплатит
200*0,95=190р
22,44,99,20,40,90,24,29,42,49,92,94.