Tìm x sao cho: 

- Hướng dẫn giải

$\left(x+5\right)\left(4-3x\right)-{\left(3x+2\right)}^2+{\left(2x+1\right)}^3=\left(2x-1\right)\left(4x^2+2x+1\right)$

$-3x^2-11x+20-9x^2-12x-4+8x^3+12x^2+6x+1=8x^3-1$

$-17x+18=0$

$x=\frac{18}{17}$

Vậy $x=\frac{18}{17}$