B

B

D

Thi tự làm nhé

A (/v/, còn lại /f/)

D (/id/, còn lại /d/)

D /ch/, còn lại /k/

Cinema
reCycle
maCHine

A

A

A

a a a

C

B

D

\(a,A+B=x^2-2x-y^2-1+\left(-2x\right)^2+3y^2-5x+y+3\\ =-x^2+2y^2-7x+y+2\\ A-B=x^2-2x-y^2-1+2x^2-3y^2+5x-y-3\\ =3x^2-4y^2+3x-y-4\)

\(b,B-D=A\\ \Rightarrow-D=A-B\\ \Rightarrow D=-\left(3x^2-4y^2+3x-y-4\right)\\ \Rightarrow D=4+y+4y^2-3x^2-3x\)

Bài 5 : 

a, \(A+B=-x^2+2y^2-7x+y+2\)

\(A-B=3x^2+3x-4y^2-4-y\)

b, \(D=B-A=-2x^2+3y^2-5x+y+3-x^2+2x+y^2+1=-3x^2+4y^2-3x+y+4\)

a) \(A+B=x^2-2x-y^2-1-2x^2+3y^2-5x+y+3=-x^2-7x+2y^2+y+2\\ A-B=x^2-2x-y^2-1-\left(-2x^2+3y^2-5x+y+3\right)\\ =x^2-2x-y^2-1+2x^2-3y^2+5x-y-3\\ =3x^2+3x-4y^2-y-4\)b)\(B-D=A\Leftrightarrow D=B-A=-\left(A-B\right)=-3x^2-3x+4y^2+y+4\)

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

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

A

B

A