b)x²(x+1)-(x+1)=(x+1)(x²-1)

d) 4x(x-2)-(x-2)=(x-2)(4x-1)

câu a bn ghi mik k hỉu

a: \(-3xy^2+x^2y^2-5x^2y\)

\(=xy\left(-3y+xy-5x\right)\)

c: \(y^2+xy+y=y\left(y+x+1\right)\)

B1 : a, M = x³-3xy(x-y)-y³-x²+2xy-y²

= ( x³-y³)-3xy(x-y) -(x²-2xy+y²)

= (x-y)(x²+xy+y²)-3xy(x-y)-(x-y)²

= (x-y) [(x²+xy+y²-3xy-(x-y)]

= (x-y)[(x²-2xy+y²)-(x-y)

= (x-y)[(x-y)²-(x-y)]

= (x-y)(x-y)(x-y-1)

= (x-y)²(x-y-1)

= 7²(7-1) = 49 . 6= 294

N = x²(x+1)-y²(y-1)+xy-3xy(x-y+1)-95

= x³+x²-(y³-y²)+xy-(3x²y-3xy²+3xy)-95

= x³+x²-y³+y²+xy-3x²y+3xy²-3xy-95

= (x³-y³)+(x²-2xy+y²)-(3x²y+y²)-(3x²y-3xy²)-95

=(x-y)(x²+xy+y²)+(x-y)²-3xy(x-y)-95

= (x-y)(x²+xy+y²+x-y-3xy)-95

= (x-y)[(x²-2xy+y²)+(x-y)]-95

= (x-y)[(x-y)²+(x-y)]-95

=(x-y)(x-y)(x-y+1)-95

= (x-y)²(x-y+1)-95

= 7²(7+1)-95=297

\(A=\left(x+y\right)^2=\left(x-y\right)^2+4xy\)

Thay x - y = 5 và xy = 3 vào ta có:

\(5^2+4\cdot3=37\)

Vậy A = 37

B = \(\left(x-y\right)^2=\left(x+y\right)^2-4xy=7^2-4\cdot12=1\)

C sai đề?

D = \(x^2-y^2-2013x-2013y\)

\(=\left(x-y\right)\left(x+y\right)-2013\left(x+y\right)\)

\(=\left(x-y\right)\left(x+y\right)-\left(x-y\right)\left(x+y\right)=0\)

E = \(x^4-y^4=\left(x^2-y^2\right)\left(x^2+y^2\right)=\left(x^2-y^2\right)\cdot0=0\)

viết bằng công thức ở chỗ \(\sum\) đi bạn

Bạn bảo cái gì cơ

a) A=x^3 + 3x^2*5 + 3x*5^2 + 5^3

       =(x+5)^3

Thay x = -10 vào biểu thức A ta được:

A  = (-10+5)^3

    =(-5)^3

    =-75

Làm tương tự nhé

\(a,x^2+7x+7y-y^2\)

\(=x^2-y^2+7\left(x+y\right)\)

\(=\left(x-y\right)\left(x+y\right)+7\left(x+y\right)\)

\(=\left(x+y\right)\left(x-y+7\right)\)

\(b,x^2-2x-9y^2+6y\)

\(=x^2-\left(3y\right)^2-2\left(x-3y\right)\)

\(=\left(x-3y\right)\left(x+3y\right)-2\left(x-3y\right)\)

\(=\left(x-3y\right)\left(x+3y-2\right)\)

\(c,x^2-xy+x^3-3x^{2y}+3x^{2y}-y^3\)

\(=x\left(x-y\right)+\left(x-y\right)\left(x^2+xy+y^2\right)\)

\(=\left(x-y\right)\left(x+x^2+xy+y^2\right)\)

giúp với trí ơi

giúp nốt trí ui

a) \(4x^2-2x-y^2-y=\left(4x^2-y^2\right)-\left(2x+y\right)\)

\(=\left(2x+y\right)\left(2x-y\right)-\left(2x+y\right)=\left(2x+y\right)\left(2x-y-1\right)\)

b) \(9x^2-25y^2-6x+10y=\left(3x-5y\right)\left(3x-5y\right)-2\left(3x-5y\right)\)

\(=\left(3x-5y\right)\left(3x+5y-2\right)\)

c) \(x^3-2x^2+2x-1=x^3-1-2x^2+2x\)

\(=\left(x-1\right)\left(x^2+x+1\right)-2x\left(x-1\right)\)

\(=\left(x-1\right)\left(x^2+x+1-2x\right)=\left(x-1\right)\left(x^2-x+1\right)\)

d) \(x^4+2x^3-4x-4=x^4-4+2x^3-4x\)

\(=\left(x^2-2\right)\left(x^2+2\right)+2x\left(x^2-2\right)=\left(x^2-2\right)\left(x^2+2+2x\right)\)