Ta có:  x²y+5xy-14y

        = y(x²+5x-14)

        = y(x+7)(x-2)

           x³-5x²-14x

        = x(x²-5x-14)

        = x(x-7)(x+2)

\(x^2y+5xy-14y\)

\(=x^2y-2xy+7xy-14y\)

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

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

\(x^3-5x^2-14x\)

\(=x^3-7x^2+2x^2-14x\)

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

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

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

á,(x+7)²-y²

= (x+7+y)(x+7-y)

b, (x+1)(x-25)

chúc bạn luôn thành công trong cuộc sống nha

a) 

\(x^2-y^2+14x+49\)

\(=\left(x^2+14x+49\right)-y^2\)

\(=\left(x^2+2.7.x+7^2\right)-y^2\)

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

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

Vậy ...

b)

 \(x^2-24x-25\)

\(=x^2-24x+144-169\)

\(=\left(x^2-24x+144\right)-169\)

\(=\left(x^2-2.12.x+12^2\right)-13^2\)

\(=\left(x-12\right)^2-13^2\)

\(=\left(x-12+13\right)\left(x-12-13\right)\)

\(=\left(x+1\right)\left(x-25\right)\)

Vậy ...

b) 3x⁴-3x³+9x³-9x²-24x²+24x-48x+48

=3x³(x-1)+9x²(x-1)-24x(x-1)-48(x-1)

=(x-1)(3x³+9x²-24x-48)

=3(x-1)(x³+3x²-8x-16)

5 x² - 5xy+2x−2y = 2x ( x - y) + 2( x - y) = 2( x + 1)( x - y)

b: =(x+2)(x+3)

b,= (x+2) (x+3)

hok tốt

a, 5x^2 +5xy - x - y 

= 5x ( x+ y ) - (x + y)

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

b, 2x^2  + 3x - 5 

= 2x^2 - 2x + 5x - 5 

= 2x( x - 1) + 5( x - 1)

= ( 2x + 5 )(x- 1 )

c; 16x - 5x^2 - 3 

c, = - ( 5x^2 - 16x + 3 )

   = - ( 5x^2 - x - 15x + 3 )

= - [ x(5x - 1 ) - 3 (5x - 1) ]

= - ( x- 3)(5x -  1 )

a) (x + 2)(x + 4).              b) 2(x + 6)(x + l).

c) 3(3x + 5)(x + l).           d) (6x -7y)(x + y).

Lời giải:

$A=x^2-8xy+15y^2=x^2-3xy-(5xy-15y^2)$

$=x(x-3y)-5y(x-3y)=(x-3y)(x-5y)$

$B=2x^2-5xy+2y^2=(2x^2-4xy)-(xy-2y^2)$

$=2x(x-2y)-y(x-2y)=(2x-y)(x-2y)$

$C=2x^2-3y^2-xy=(2x^2+2xy)-(3y^2+3xy)$

$=2x(x+y)-3y(y+x)=(x+y)(2x-3y)$

a,5xy+z-5x-yz=(5xy-5x)-(yz-z)=5x(y-1)-z(y-1)=(y-1)(5x-z)                                                                      b, y²(a-b)+b-a=y²(a-b)-a(a-b)=(y²-1)(a-b)=(y-1)(y+1)(a-b)