Đáp án + Giải thích các bước giải:
`+) 25x^2 -10xy + y^2 = (5x - y)^2`
`+) 9x^2 - y^2 = (3x - y)(3x+y)`
`+) x^2+6xy+9y^2 = (x+3y)^2`
`+) x^2 - 36y^2 = (x-6y)(x+6y)`
`+) (5x-1)^2 - 4x^2 = (5x-1-2x)(5x-1+2x) = (3x-1)(7x-1)`
`+) (2x+3)^2 - 25x^2 = (2x+3-5x)(2x+3+5x)=(3-3x)(7x+3)`
`+) (5x+2y)^2 -(3x-2y)^2 = (5x+2y+3x-2y)(5x+2y-3x+2y) = 8x(2x+4y)`
`+)(7x+3y)^2 -(x-3y)^2 = (7x+3y+x-3y)(7x+3y-x+3y) = 8x(6x+6y)`
`+) 125+150x+6x^2+8x^3 = (5+2x)^3`
`+) y^3 + 12y^2 +48y+64 = (y+4)^3`
`+) 8x^3 - y^3 = (2x-y)(4x^2 + 2xy + y^2)`
`+) x^3 + 125y^3 = (x+5y)(x^2-5xy + 25y^2)`
Áp dụng :
`+) A^2 +-2AB+B^2=(A+-B)^2`
`+) A^2-B^2=(A+B)(A-B)`
`+) A^3+-B^3=(A+-B)(A^2+-AB+B^2)`
`+) A^3+3A^2B+3AB^2+B^3=(A+B)^3`
