\(x^2-1=\left(x+1\right)\left(x-1\right)\)(Nhớ k cho mình với nhé!)

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

x² - 1 = x² - x + x - 1 = x . (x - 1) + (x - 1) = (x - 1) . (x + 1)

a, y(x+1+8+8)

y(x+17)

b, x(x-1)

a) xy + x + 8y + 8

= x ( y + 1 ) + 8 ( y + 1 )

= ( y + 1 ) . ( x + 8 )

b) x² - 1  

= x² - x + x - 1 

= x ( x - 1 ) + ( x - 1 )

= ( x - 1 ) . ( x + 1 )

\(a\left(x-1\right)+b\left(1-x\right)=a\left(x-1\right)-b\left(x-1\right)=\left(x-1\right)\left(a-b\right)\)

a) ( x + 1) + b ( 1 - x )

= ( x + 1 ) - b( x-   1 )

= ( 1 - b )( x- 1 )

**** 

a(x-1) + b(1-x)

= a(x-1) - b(x-1)

= (a-b)(x-1)

Nhấn đúng cho mk nha!!!!!!!!!

x³-2x²-5x=x(x²-2x-5)

\(x^3-2x^2-5x=x\left(x^2-2x-5\right)\)

a. xy+x+8y+8

= x(y+1)+8(y+1)

= (y+1)(x+8)

b. x²-x-2/3x+2/3

= x(x-1)-2/3(x-1)

= (x-1)(x-2/3)

c. x²-1

= x²-1²

= (x+1)(x-1)

a) xy + x + 8y + 8

= x.(y + 1) + 8.(y + 1)

= (y + 1).(x + 8)

b) \(x^2-x-\frac{2}{3}.x+\frac{2}{3}\)

\(=x.\left(x-1\right)-\frac{2}{3}.\left(x-1\right)\)

\(=\left(x-1\right).\left(x-\frac{2}{3}\right)\)

c) x² - 1

= x² + x - x - 1

= x.(x + 1) - (x + 1)

= (x + 1).(x - 1)

a) (xy+x) +(8y+8)=x(y+1)+8(y+1)=(x+8)(y+1)

b) (x²-x) -(2/3x-2/3)=x(x-1)+2/3(x-1)=(x+2/3)(x-1)

c) x²-1= (x-1)(x+1)

\(x^2-xy-xy+y^2\)

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

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

\(\left(x-y\right)\times\left(x-y\right)\)

ta có:

\(x^2-xy-xy+y^2\)

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

\(=\left[x.\left(x-y\right)\right]-\left[y.\left(x-y\right)\right]\)

\(=\left(x-y\right).\left(x-y\right)\)