1.分解因式：（2x-1)²-(x+2)²2.分解因式（x²+4)²-16x²3.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.分解因式：（2x-1)²-(x+2)²2.分解因式（x²+4)²-16x²3.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.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

1.分解因式：（2x-1)²-(x+2)²2.分解因式（x²+4)²-16x²3.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)