Giải bài 2 trang 16

Đề bài

Thực hiện phép tính:

a) $\left(39x^5{y}^7\right):\left(13x^{2}y\right)$                           

b) $\left(x^2{y}^2+\frac{1}{6}{x}^3{y}^2-x^5{y}^4\right):\left(\frac{1}{2}x{y}^2\right)$

Lời giải chi tiết

a)

$\left(39x^5{y}^7\right):\left(13x^{2}y\right)=\left(39:13\right).\left(x^5:x^2\right).\left(y^7:y\right)=3x^3{y}^6$

b)

$\begin{array}{c}\left(x^2{y}^2+\frac{1}{6}{x}^3{y}^2-x^5{y}^4\right):\left(\frac{1}{2}x{y}^2\right)\\ =\left(x^2{y}^2\right):\left(\frac{1}{2}x{y}^2\right)+\left(\frac{1}{6}{x}^3{y}^2\right):\left(\frac{1}{2}x{y}^2\right)+\left(-x^5{y}^4\right):\left(\frac{1}{2}x{y}^2\right)\\ =2x+\frac{1}{3}{x}^2-2x^4{y}^2\end{array}$