tim tich cua hai don thuc sau:
2/3*x^2*y*z va -3*x*y^2
tim tich cua hai don thuc
-2*x^2*y^2*z va -1/3*x^2*y^3
\(\left(-2x^2y^2z\right).\left(-\dfrac{1}{3}x^2y^3\right)\)
\(=-2.x^2.y^2.z^2.\dfrac{-1}{3}.x^2.y^3\)
\(=\dfrac{2}{3}x^4y^5z^2\)
Ta có: \(-2x^2y^2z\cdot\dfrac{-1}{3}x^2y^3\)
\(=\left(-2\cdot\dfrac{-1}{3}\right)\cdot\left(x^2\cdot x^2\right)\cdot\left(y^2\cdot y^3\right)\cdot z\)
\(=\dfrac{2}{3}x^4y^5z\)
`(-2.x^2.y^2.z).(-1/3.x^2.y^3)`
`=-2/3.x^{2+2}.y^{2+3}.z`
`=-2/3x^4y^5x`
NHan cac don thuc sau va tim bac va he so cua don thuc nhan duoc:
(\(\frac{1}{3}\)x\(^3\)y).(-xy)\(^2\)
NHan cac don thuc sau va tim bac va he so cua don thuc nhan duoc:
(\(\dfrac{1}{3}\)x\(^3\)y).(-xy)\(^2\)
\(\left(\dfrac{1}{3}x^3y\right)\left(-xy\right)^2=\left(\dfrac{1}{3}x^3y\right).x^2y^2=\dfrac{1}{3}x^5y^3\)
Bậc: 5
Hệ số: \(\dfrac{1}{3}\)
NHan cac don thuc sau va tim bac va he so cua don thuc nhan duoc:
(\(\frac{1}{3}\)x\(^3\)y).(-xy)\(^2\)
ta có (sau khi nhân) đơn thưc
-\(\frac{1}{3}\)x5y3
bậc là 5. hệ số -1/3
cho don thuc A=19/5 xy^2(x^3y)(-3x^13y^5)^0
a, thu gon don thuc A
b, tim he so va bac cua don thuc
c, tinh gia tri cua don thuc tai x=1, y=2
a: \(A=\dfrac{19}{5}xy^2\cdot x^3y=\dfrac{19}{5}x^4y^3\)
b: Hệ số là 19/5 và bậc là 7
c: Khi x=1 và y=2 thì \(A=\dfrac{19}{5}\cdot1^4\cdot2^3=\dfrac{19}{5}\cdot8=\dfrac{152}{5}\)
thu gon don thuc tim bac he so cua da thuc A=x^3 *(-5/4*x^2*y)*(2/5*x^3*y^4)
A=x^3*(-5/4x^2y)*(2/5x^3y^4)
A=(1*-5/4*2/5)*(x^3*x^2*x^3*y*y^4)
A=-1/2x^8y^5
bậc:13
hệ số:-1/2
Tim tich cua hai so x va y. Biet rang neu tang x len 3 lan va y len 2 lan thi dc tich moi bang 72
ta co :(Xx3)x(Yx2)=72
Xx3xYx2=72
(XxY)x(3x2)=72
XxYx6=72
XxY=72/6=12
vay tich cua x va y la 12
Cho don thuc A=(-2xy)-4/5x^2y^3 a,Thu gon don thuc tren ,cho biet phan he so va phan bien ,tim bac cua don thuc b,Tinh gia trim cua don thuc tai x=1,y=-1
a, P=-3(x^3.x)(y^2.y^3)
=-3x^4y^5
b, Thay x=-1 , y=2 vào đơn thức P . Ta có :
P=-3.(-1)^4.2^5
P=3.1.32
P=96
Cho don thuc A=(-2xy)-4/5x^2y^3 a,Thu gon don thuc tren ,cho biet phan he so va phan bien ,tim bac cua don thuc b,Tinh gia trim cua don thuc tai x=1,y=-1