Question

phân tích đa thức thành nhân tử :

x²y - 4y

x² - y² - 2x + 1

5x² + 5xy - x - y

gấp sẽ tick ạ, đầy đủ ạ

Answer 1

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

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

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

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

c,\(5x^2+5xy-x-y=5x\left(x+y\right)-\left(x+y\right)\)

                                            \(=\left(5x-1\right)\left(x+y\right)\)

 

Answer 2

x²y - 4y = y( x² - 4 ) = y( x - 2 )( x + 2 )

x² - y² - 2x + 1 = ( x² - 2x + 1 ) - y² = ( x - 1 )² - y² = ( x - 1 - y )( x - 1 + y )

5x² + 5xy - x - y = ( 5x² + 5xy ) - ( x + y ) = 5x( x + y ) - ( x + y ) = ( x + y )( 5x - 1 )

Answer 3

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

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

\(5x^2+5xy-x-y=5x\left(x+y\right)-\left(x+y\right)=\left(x+y\right)\left(5x-1\right)\)