Question

1) 13 + x²(x – 9) <(x - 3) + 11;
2) 26 + (2 + x)^3 < x^2 (6 + x);
3) 3x - x²(15 + x) > -(x + 5)^3 – 4x;
4) (4 + x)^3 - 6x < x²(x + 12) + 1.​

Answer 1

1)13+x²(x-9)≤(x-3)³+11

13+x³-9x²≤x³-3*x²*3+3*x*3²-3³

13+x³-9x²≤x³-9x²+27x-27

x³-9x²-x³+9x²-27x≤-27-13

-27x≤-40

x≤1 13/27

(-∞;1 13/27]

2)26+(2+x)³26+2³+3*2²*x+3*2*x²+x³<6x²+x³

26+8+12x+6x²+x³<6x²+x³

12x+6x²+x³-6x²-x³<-26-8

12x<-34

x<-2 10/12

(-∞;-2 10/12)

Объяснение: