Đáp án + Giải thích các bước giải:
`a)`
`(x-3)²-(5-2x)²`
`= (x-3-5+2x)(x-3+5-2x)`
`= (3x-8)(2-x)`
`b)`
`(x+y)²-x²+4xy-4y²`
`= (x+y)²-(x²-4xy+4y²)`
`= (x+y)²-(x-2y)²`
`= (x+y-x+2y)(x+y+x-2y)`
`= 3y(2x-y)`
`c) (x+y)³-(x-y)³`
`= x³+3x²y+3xy²+y³-x³+3x²y-3xy²+y³`
`= 6x²y+2y³`
`d) x²-4x+4-y²-6y-9`
`= (x²-4x+4)-(y²+6y+9)`
`= (x-2)²-(y+3)²`
`= (x-2-y-3)(x-2+y+3)`
`= (x-y-5)(x+y+1)`
`e) 4x²-12xy+9y²`
`= (2x-3y)²`
`f) 27x³-0,001`
`=(3x)³-(0,1)³`
`= (3x-0,1)(9x²+0,3x+0,01)`
