Question

Answer 1

\(P=\dfrac{A}{B}=\dfrac{4x^5y^3+12x^3y^4}{6x^3y}=\dfrac{x^3y^3\left(4x^2+12y\right)}{6x^3y}=\dfrac{4x^2+12y}{6}\cdot y^2\)

\(=\dfrac{4\left(x^2+3y\right)}{6}\cdot y^2=\dfrac{2}{3}\left(x^2+3y\right)\cdot y^2\)

Thay x=2;y=3 vào P, ta được:

\(P=\dfrac{2}{3}\left(2^2+3\cdot3\right)\cdot3^2=\dfrac{2}{3}\cdot9\cdot\left(4+9\right)\)

\(=6\cdot13=78\)

Answer 2

\(P=A:B=\left(4x^5y^3+12x^3y^4\right):6x^3y=\dfrac{2}{3}x^2y^2+2y^3\)

tại \(x=2;y=3\)

\(A=\dfrac{2}{3}.2^2.3^2+2.3^3=78\)