Сos(x/2) = 1/2
x/2 = ±π/3 + 2πn, n ∈ Z
x = ±2π/3 + 4πn, n ∈ Z
0 < ±2π/3 + 4πn < 4π, n ∈ Z
n = 0
x₁ = 2π/3
n = 1
x₂ = - 2π/3 + 4π = 10π/3
Ответ:x = ±2π/3 + 4πn, n ∈ Z; 2π/3; 10π/3
А) -5,123 < -5,1231
б) 1,2112 < 1,2121
14. х = 3х
х = 0
Ответ: 0
15. х^2 - 3х + 2 = 0
D = 9 - 8 = 1
x1 = 3 - 1 / 2 = 1
x2 = 3 + 1 / 2 = 2
b / m + 1
b = 2
m = 1
2 / 1 + 1 = 3
Ответ: 3
16. 8х^4 + х^3 + 64х + 8 = 0
Пусть х^3 = у, тогда (8xy+y) + (64x+8) = 0
y(8x+1) + 8(8x+1) = 0
(y+8)(8x+1) = 0
y+8 = 0
y = -8
8x+1 = 0
8x = -1
x = -1/8
x^3 = -8, корней нет
Ответ: -1/8
1)(3-√2)(3+√2)/5=(9-2)/5=7/5=
<em><u>1,4</u></em>2)Приводим к одному знаменателю:
700/900 >300/900 >171/900===>
<em><u>7/9>1/3>0,19
</u></em><em><u>
</u></em><u>
</u>
3)4,8-(11*5)/5*2=4,8-11/2=4,8-5,5=
<em><u>-0,7
</u></em>4)3,9*<u />
=
<em><u>0,39</u></em><em><u>Удачи в решении задач!</u></em>