4.7
B)
3(x-1) = 2(x+2)
3x-3 = 2x +4
x = 7
Г)
3(х-5) - 2(x+4) = -5x +1
3x-15 - 2x - 8 = - 5x +1
3x - 2x + 5x = 1 + 15 + 8
6x = 24
x = 4
4.8
1. x=1
2. x = -6
3. x=1
4. x=5
Sin4xcos4x=1/4
1/2sin8x=1/4
sin8x=1/2
8x=(-1)^n*sin(pi/6)+pi*n, n c Z
x=(-1)^n*sin(pi/6)/8 + pi*n/8, n c Z
Берем х=1 5 х 1=-10 х=-2 (меньше 5)
х=2 5 х 2 = -10 х=-1
х = -1 5 х (-1)=-10 х=2
х=-2 5 х (-2)=-10 х=1
Удачи!