Đáp án:
1) \( - 38x - 34\)
Giải thích các bước giải:
\(\begin{array}{l}
1)2\left( {{x^2} - 2x + 1} \right) - 4\left( {9 + 6x + {x^2}} \right) + 2{x^2} - 10x\\
= 2{x^2} - 4x + 2 - 36 - 24x - 4{x^2} + 2{x^2} - 10x\\
= - 38x - 34\\
2)2{\left( {3x - 2} \right)^2} - \left( {4 - 10x} \right)\left( {2 - 3x} \right)\\
= 2\left( {9{x^2} - 12x + 4} \right) - \left( {8 - 12x - 20x + 30{x^2}} \right)\\
= 18{x^2} - 24x + 8 - 30{x^2} + 32x - 8\\
= - 12{x^2} + 8x\\
3)\left( {6{x^2} + 4x - 3x - 2} \right)\left( {3 - x} \right)\\
= \left( {6{x^2} + x - 2} \right)\left( {3 - x} \right)\\
= 18{x^2} - 6{x^3} + 3x - {x^2} - 6 + 2x\\
= - 6{x^3} + 17{x^2} + 5x - 6\\
4)\dfrac{2}{5}xy\left( {{x^2}y - 5x + 10y} \right)\\
= \dfrac{2}{5}{x^3}{y^2} - 2{x^2}y + 4x{y^2}
\end{array}\)
