1.1y=3x²-7x³+51.1y=(x+2)(2x³-x)

{ 1 * y = 3 * x ^ 2 - 7 * x ^ 3 + 51;

1 * y = (x + 2) * (2 * x ^ 3 - x); 

3 * x ^ 2 - 7 * x ^ 3 + 51 = (x + 2) * (2 * x ^ 3 - x); 

3 * x ^ 2 - 7 * x ^ 3 + 51 = x * 2 * x ^ 3 - x * x + 2 * 2 * x ^ 3 - 2 * x; 

3 * x ^ 2 - 7 * x ^ 3 + 51 = 2 * x ^ 4 - x ^ 2 + 4 * x ^ 3 - 2 * x; 

3 * x ^ 2 - 7 * x ^ 3 + 51 - 2 * x ^ 4 + x ^ 2 - 4 * x ^ 3 + 2 * x = 0;  

- 2 * x ^ 4  - 11 * x ^ 3 + 4 * x ^ 2 + 2 * x  + 51 = 0;  

2 * x ^ 4 + 11 * x ^ 3 - 4 * x ^ 2 - 2 * x - 51 = 0; 

x1 = - 0.61 + 1.49 * i; 

x2 = - 0.61 - 1.49 * i; 

x3 = 1.66; 

x4 = - 5.93.