Решите уравнение 1/9х+7/18х-11/27х=2 1/2

1/9х+7/18х-11/27х=2 1/2 х-7/3=-2 6/54х+21/54х-22/54х=5/2 х= -2+7/3 5/54х=5/2 х=-6/3+7/3 54х=2 х=1/3 х=2/54 х=1/27

1) cos t≥1/3;
-arccos 1/3+2πn≤t≤arccos 1/3+2πn, n∈Z.

2) cos t≤-1/2 ;
arccos (-1/2)+2πn≤t≤2π-arccos (-1/2)+2πn, n∈Z;
π-arccos 1/2+2πn≤t≤2π-(π-arccos 1/2)+2πn, n∈Z;
π-π/3+2πn≤t≤π+π/3+2πn, n∈Z;
2π/3+2πn≤t≤4π/3+2πn, n∈Z.

3) sin t≤-1/2;
-π-arcsin(-1/2)+2πn≤t≤arcsin(-1/2)+2πn, n∈Z;
-π+arcsin 1/2+2πn≤t≤-arcsin 1/2+2πn, n∈Z;
-π+π/6+2πn≤t≤-π/6+2πn, n∈Z;
-5π/6+2πn≤t≤-π/6+2πn, n∈Z.

4) sin t>√3/2;
arcsin √3/2+2πn<t<π-arcsin √3/2+2πn, n∈Z;
π/3+2πn≤t≤π-π/3+2πn, n∈Z;
π/3+2πn≤t≤2π/3+2πn, n∈Z.

5) sin t≤2/3;
-π-arcsin 2/3+2πn≤t≤arcsin 2/3+2πn, n∈Z.

6) sin t≥√2/2;
arcsin √2/2+2πn≤t≤π-arcsin √2/2+2πn, n∈Z;
π/4+2πn≤t≤π-π/4+2πn, n∈Z;
π/4+2πn≤t≤3π/4+2πn, n∈Z.

1) 3x - 4 = 8
3x = 12
x = 4

2)12 - 2x = - 10
- 2x = - 22
x = 11

3)2x + 3 = 10
2x = 7
x = 3,5

4) 14x - 7 = 28
14x = 35
x = 2,5

5) (x - 3)(15 - x) = 0
15x - x² - 45 + 3x = 0
- x² + 18x - 45 = 0
x² - 18x + 45 = 0
D = b² - 4ac = 324 - 4×45 = 324 - 180 = √144= 12
x₁ = 18 + 12/2 = 15
x₂ = 18 - 12/2 = 3

6) (2x - 20)(3 + 3x) = 0
6x + 6x² - 60 - 60x = 0
6x² - 54x - 60 = 0
D = 2916 - 4×6 × ( - 60) = 2916 + 1440 = 4356
x₁ = 54 + 66/ 12 = 10
x₂ = 54 - 66/12 = - 1

7)( 12 - 3x)(25 - 5x) =0
300 -  60x - 75x + 15x² = 0
15x² - 135x + 300 = 0
D = 18225 - 4 × 15 × 300 = 18225 - 18000 = √225 = 15
x₁ = 135 + 15/30 = 5
x₂ = 135 - 15/30 = 4