Решение
1) sinx = - 1/2
x = (-1)^n *arcsin(-1/2) + πn, n ∈ Z
x = (-1)^(n+1) *arcsin(1/2) + πn, n ∈ Z
x = (-1)^(n+1) *(π/6)<span> + πn, n ∈ Z
</span>2) 3tgx = 0
tgx = 0
x = πk, k ∈ Z
3) cos4x = 0
4x = π/2 + πn, n ∈ Z
x = π/8 + (πn)/4, n ∈ Z
4) cos(3x - π/6) = - 1
3x - π/6 = π + 2πk, k ∈ Z
<span>3x = π/6 + π + 2πk, k ∈ Z
</span>3x = 7π/6 + <span>2πk, k ∈ Z
x = 7</span>π/18 + (2πk)/3, k ∈ Z
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Думаю, так. На счёт последнего сомнения)
3 м2 = 3000000 мм2
5дм2 40см2 = 50000 + 4000 = 54000 мм2
700 дм2 = 7 м2
9000 дм2 = 90 м2
845 см2 = 8,45 дм2
6 8 48 2. 24. 28
9. 12. 108. 3. 36. 108
15. 18. 270. 3. 90. 270
24. 60. 1440. 12. 120. 1440