Question

giúp mk nha khẩn cấp !!

Answer 1

\(a,A=\dfrac{-1}{3}\left(-xy^4\right)^2\left(-xy^3\right)=\dfrac{-1}{3}.x^2.y^8.\left(-x\right).y^3=\dfrac{1}{3}x^3y^{11}\)

Bậc: 14

Hệ số:\(\dfrac{1}{3}\)

Biến:x³y¹¹

\(B=-4x^3y^3\left(\dfrac{y^2}{2}\right)^3=-4x^3y^3.\dfrac{y^6}{8}=\dfrac{-1}{2}x^3y^9\)

Bậc: 12

Hệ số:\(\dfrac{-1}{2}\)

Biến:x³y⁹

b, Thay x=0,5,y=-1 vào A ta có:
\(A=\dfrac{1}{3}x^3y^{11}=\dfrac{1}{3}.0,5^3.\left(-1\right)^{11}=\dfrac{1}{3}.\dfrac{1}{8}.\left(-1\right)=\dfrac{-1}{24}\) Thay x=0,5,y=-1 vào B ta có: \(B=\dfrac{-1}{2}x^3y^9=\dfrac{-1}{2}.0,5^3.\left(-1\right)^9=\dfrac{-1}{2}.\dfrac{1}{8}.\left(-1\right)=\dfrac{1}{16}\)