1.分解因式:(2x-1)²-(x+2)²
来源:学生作业帮 编辑:作业帮 分类:数学作业 时间:2024/09/04 15:10:11
1.分解因式:(2x-1)²-(x+2)²
2.分解因式(x²+4)²-16x²
3.分解因式:(1)(2m-n)²-(m-2n)²
(2)25(a+b)²-40(a+b)(a-b)+16(a-b)²
(3)8(x²-2y²)-x(7x+y)+xy
2.分解因式(x²+4)²-16x²
3.分解因式:(1)(2m-n)²-(m-2n)²
(2)25(a+b)²-40(a+b)(a-b)+16(a-b)²
(3)8(x²-2y²)-x(7x+y)+xy
1.(2x-1)²-(x+2)²
=[(2x-1)+(x+2)]*[(2x-1)-(x+2)]
=(3x+1)(x-3)
2.(x²+4)²-16x²
=[(x²+4)+4x]*[(x²+4)-4x]
=(x+2)²*(x-2)²
3.(1)(2m-n)²-(m-2n)²
=[(2m-n)+(m-2n)]*[(2m-n)-(m-2n)]
=3(m-n)(m+n)
(2)25(a+b)²-40(a+b)(a-b)+16(a-b)²
=[5(a+b)-4(a-b)]²
=(a+9b)²
(3)8(x²-2y²)-x(7x+y)+xy
=8x²-16y²-7x²-xy+xy
=x²-16y²
=(x+4y)(x-4y)
=[(2x-1)+(x+2)]*[(2x-1)-(x+2)]
=(3x+1)(x-3)
2.(x²+4)²-16x²
=[(x²+4)+4x]*[(x²+4)-4x]
=(x+2)²*(x-2)²
3.(1)(2m-n)²-(m-2n)²
=[(2m-n)+(m-2n)]*[(2m-n)-(m-2n)]
=3(m-n)(m+n)
(2)25(a+b)²-40(a+b)(a-b)+16(a-b)²
=[5(a+b)-4(a-b)]²
=(a+9b)²
(3)8(x²-2y²)-x(7x+y)+xy
=8x²-16y²-7x²-xy+xy
=x²-16y²
=(x+4y)(x-4y)