a: \(=\dfrac{-1}{4}x^4y^5\)
Bậc là 9
b: \(=x^3y^6\)
Bậc là 9
\(a,-\dfrac{1}{5}x^3y^2\dfrac{5}{4}xy^3=\left(-\dfrac{1}{5}.\dfrac{5}{4}\right)\left(x^3.x\right)\left(y^2.y^3\right)=\dfrac{-1}{4}x^4y^5\)
Bậc là 9
\(b,-3xy^4\left(-\dfrac{1}{3}\right)x^2y^2=\left[\left(-3\right)\left(-\dfrac{1}{3}\right)\right]\left(x.x^2\right)\left(y^4.y^2\right)=x^3y^6\)
Bậc là 9