sin(x/2- π/6)+1=0
1 = sin(π/2)
sin(x/2 - π/6) + sin(π/2) = 0
sin(x/2 - π/6) = -sin(π/2)
sin(x/2 - π/6) = sin(-π/2)
x/2 - π/6 = (3x - π)/6
(3x - π)/6 = -π/2
3x - π + 3π = 0
3x +2π = 0
3x = -2π
x = -2π/3
Ответ: -2π/3
Раскрываем скобки:
2х-7х-1=8
-5х=9
х= -9/5= -1 4/5.
1)=4x^2-y^2-4x^2+4xy-y^2=4xy-2y^2
2)=y^2-16x^2+y^2-8x+16x^2=2y^2-8x
= -3ху+ 15ха-14аb+21ac-24pa+36pb+84pc