Ta có: x2yz.(2xy)2z = x2yz.4x2y2.z = 4(x2.x2)(y.y2)(z.z) = 4x4y3z2

Nhóm các đơn thức đồng dạng:

Ta có: -2/3 xy2z.(-3x2y)2 = -2/3 xy2z.9x4y2

= (-2/3 .9)(x.x4).(y2.y2).z = -6x5y4z

a) \(-\dfrac{2}{3}xy^2z.\left(-3x^2y\right)^2\)

= \(-\dfrac{2}{3}xy^2z.9x^4y^2\)

= \(-6x^5y^4z\)

b) \(x^2yz.\left(2xy\right)^2z\)

= \(x^2yz.4x^2y^2z\)

= \(4x^4y^3z^2\)

\(A=4x^2y+\dfrac{14}{15}xy^2-2xy-\dfrac{2}{3}\)            bậc : 3

\(B=2xy^2z-1\)                  bậc :4

+ Thu gọn :

\(A=4x^2y+\dfrac{14}{15}xy^2-2xy-\dfrac{2}{3}\)

\(B=2xy^2z-1\)

+ Bậc

Đa thức \(A\) có 4 hạng tử :

  \(4x^2y\) có bậc \(3\)

 \(\dfrac{14}{15}xy^2\) có bậc \(3\)

 \(-2xy\) có bậc \(2\)

 \(-\dfrac{2}{3}\) có bậc \(0\)

Đa thức \(B\) có \(2\) hạng tử :

   \(2xy^2z\) có bậc \(4\)

   \(-1\) có bậc \(0\)

`2/3xy^2z.(-3x^3y^3)`

`=-2x^{1+3}y^{2+3}z`

`=-2x^4y^5z`

2/3xy^2z.(-3).x^3.y^3

=(2/3.(-3)).(x.x^3).(y^2.y^3).z

=-2.x^4.y^5.z

a: A = -2xy + 3/2xy^2 + 1/2xy^2 + xy = -2xy + 2xy^2 + xy = 2xy^2 - xy

b: B = xy^2z + 2xy^2z - xyz - 3xy^2z + xy^2z = 3xy^2z - xyz

c: C = 4x^2y^3 + x^4 - 2x^2 + 6x^4 - x^2y^3 = 7x^4 + 3x^2y^3 - 2x^2

d: D = 3/4xy^2 - 2xy - 1/2xy^2 + 3xy = 5/4xy^2 + xy

e: E = 2x^2 - 3y^3 - z^4 - 4x^2 + 2y^3 + 3z^4 = -2x^2 - y^3 + 2z^4

f: F = 3xy^2z + xy^2z - xyz + 2xy^2z - 3xyz = 6xy^2z - 2xyz

a: A=-2xy+3/2xy^2+1/2xy^2+xy

=-2xy+xy+3/2xy^2+1/2xy^2

=2xy^2-xy

b: \(B=xy^2z+2xy^2z-xyz-3xy^2z+xy^2z\)

\(=xy^2z\left(1+2-3+1\right)-xyz=xy^2z-xyz\)

c: \(=4x^2y^3-x^2y^3+x^4+6x^4-2x^2\)

\(=7x^4-x^2+3x^2y^3\)

d: \(=\dfrac{3}{4}xy^2-\dfrac{1}{2}xy^2+3xy-2xy\)

=1/4xy^2+xy

e: \(=2x^2-4x^2-3y^3+2y^3+3z^4-z^4\)

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

f: \(=xy^2z+3xy^2z+2xy^2z-xyz-3xyz\)

\(=6xy^2z-4xyz\)