\(N=x^3-y^3+x^2+y^2-2xy-3xy\left(x-y\right)-95\)
\(=\left(x-y\right)^3+3xy\left(x-y\right)+\left(x-y\right)^2-3xy\left(x-y\right)-95\)
\(=\left(x-y\right)^3+\left(x-y\right)^2-95\)
\(=7^3+7^2-95\)
\(=297\)
\(N=x^3-y^3+x^2+y^2-2xy-3xy\left(x-y\right)-95\)
\(=\left(x-y\right)^3+3xy\left(x-y\right)+\left(x-y\right)^2-3xy\left(x-y\right)-95\)
\(=\left(x-y\right)^3+\left(x-y\right)^2-95\)
\(=7^3+7^2-95\)
\(=297\)
làm hộ tôi bài cho x-y = 7 tính N= $x^2\left(x+1\right)-y^2\left(y-1\right)+xy-3xy\left(x-y+1\right)-95$x2(x+1)−y2(y−1)+xy−3xy(x−y+1)−95
Cho x-y=7 . Giá trị của biểu thức
H=x^2(x+1) - y^2(y-1) + xy - 3xy(x-y+1) - 95 là:
\(H=x^2\left(x+1\right)-y^2\left(y-1\right)+xy-3xy\left(x-y+1\right)-95\) 95
Cho x-y=7
Tính:
a/ \(A=x^3-3xy\left(x-y\right)-y^3-x^2-2xy-y^2\)
b/ \(B=x^2\left(x+1\right)-y^2\left(y-1\right)+xy-3xy\left(x-y+1\right)-95\)
Cho x-y=7 Tính
\(H=x^2\cdot\left(x+1\right)-y^2\cdot\left(y-1\right)+xy-3xy\cdot\left(x-y+1\right)-95\)
cho x-y=7.Tính: \(^{^{x^2\left(x+1\right)-y^2\left(y-1\right)+xy\left(x-y+1\right)-95}}\)
1. Rút gọn biểu thức:
\(B=2\left(2x+3y\right)\left(2x-3y\right)-\left(2x-1\right)^2-\left(3y-1\right)^2\)
\(C=x^2\left(x+1\right)-y^2\left(y-1\right)+xy-3xy\left(x-y+1\right)-95\)
Tính giá trị biểu thức:
\(A=8x^3-36x^2+54x+27\) tại x = 42
\(B=x^4+y^4\)với x+y=3, xy = 2
\(C=x^2\left(x+1\right)-y^2\left(y-1\right)+xy-3xy\left(x-y+1\right)-95\)với x - y = 7
Giúp mk vs!!! Mk đang rất gấp!!!
Câu 4: Cho x - y= 7. Tính giá trị của các biểu thức:
a) M = \(x^3\) -\(3xy\left(x-y\right)\)-\(y^3\)-\(x^2\)+ \(2xy\)- \(y^2\)
b) N= \(x^2\)\(\left(x+1\right)\)- \(y^2\)\(\left(y-1\right)\)+\(xy\)- \(3xy\left(x+y+1\right)\)-95
Rút gọn biểu thức:
a) \(A=\left(x-y\right)^3+\left(y+x\right)^3+\left(y-x\right)^3-3xy\left(x+y\right)\)
b) \(B=3x^2\left(x+1\right)\left(x-1\right)-\left(x^2-1\right)\left(x^4+x^2+1\right)+\left(x^2-1\right)^3\)
c) \(C=\left(x+y\right)\left(x^2-xy+y^2\right)+\left(x-y\right)\left(x^2+xy+y^2\right)-2x^3\)
d) \(D=\left(x+1\right)^3+\left(x-1\right)^3+x^3-3x\left(x+1\right)\left(x-1\right)\)