1 * x + 3ix + 2y - 5iy = 7 + i;
x + 2y = 7; 3x + 6y = 21;
i: 3x - 5y = 1;
11y = 20;
y = 20/11;
x + 40/11 = 7;
x = 37/11; y = 20/11.
1.
x=7,13 +-0,04
x min = 7,13-0,04 = 7,09
x max = 7,13+0,04 = 7,17
x∈[7,09; 7,17]
2.
y = (x max + x min) / 2 = (5,782 + 4,138) / 2 = 4,96
a = x max - y = y - x min = 5,782 - 4,96 = 0,822
1)log2(x)<4 озд:x>0
x<16
x∈(0;16)
2)log1/3(x)≥3 одз:x>0
x≤1/27
x∈(0;1/27]
3)log1/3(x-1)≤-1 одз:x>1
x-1≥3
x≥4
x∈[4:+∞)