1.thực hiện phép tính a.(8x^2 y+10xy^2-6xy):2xy b.(3x^2-4x).(2x-6) 2.x^3+8:(x^2-2x+4)=x+2 đúng hay sai 07/09/2021 Bởi Mackenzie 1.thực hiện phép tính a.(8x^2 y+10xy^2-6xy):2xy b.(3x^2-4x).(2x-6) 2.x^3+8:(x^2-2x+4)=x+2 đúng hay sai
Đáp án: \(\begin{array}{l}Bai\,\,1:\\a)\,\,\,4x + 5y – 3\\b)\,\,\,6{x^3} – 18{x^2} – 8{x^2} + 24x\\Bai\,\,2:\,\,Sai.\end{array}\) Giải thích các bước giải: \(\begin{array}{l}Bai\,\,1:\\a)\,\,\left( {8{x^2}y + 10x{y^2} – 6xy} \right):2xy\\ = 2xy\left( {4x + 5y – 3} \right):2xy\\ = 4x + 5y – 3.\\b)\,\,\left( {3{x^2} – 4x} \right)\left( {2x – 6} \right) = 6{x^3} – 18{x^2} – 8{x^2} + 24x.\\Bai\,\,\,2:\\{x^3} + 8:\left( {{x^2} – 2x + 4} \right) = x + 2\,\,\,sai\\Sua\,\,\,lai:\,\,\,\left( {{x^3} + 8} \right):\left( {{x^2} – 2x + 4} \right)\\ = \left( {x + 2} \right)\left( {{x^2} – 2x + 4} \right):\left( {{x^2} – 2x + 4} \right) = x + 2.\end{array}\) Bình luận
Đáp án:
\(\begin{array}{l}
Bai\,\,1:\\
a)\,\,\,4x + 5y – 3\\
b)\,\,\,6{x^3} – 18{x^2} – 8{x^2} + 24x\\
Bai\,\,2:\,\,Sai.
\end{array}\)
Giải thích các bước giải:
\(\begin{array}{l}
Bai\,\,1:\\
a)\,\,\left( {8{x^2}y + 10x{y^2} – 6xy} \right):2xy\\
= 2xy\left( {4x + 5y – 3} \right):2xy\\
= 4x + 5y – 3.\\
b)\,\,\left( {3{x^2} – 4x} \right)\left( {2x – 6} \right) = 6{x^3} – 18{x^2} – 8{x^2} + 24x.\\
Bai\,\,\,2:\\
{x^3} + 8:\left( {{x^2} – 2x + 4} \right) = x + 2\,\,\,sai\\
Sua\,\,\,lai:\,\,\,\left( {{x^3} + 8} \right):\left( {{x^2} – 2x + 4} \right)\\
= \left( {x + 2} \right)\left( {{x^2} – 2x + 4} \right):\left( {{x^2} – 2x + 4} \right) = x + 2.
\end{array}\)