初中 因式分解!①(x^2-5)^2-16x^2②4yx^3+4(xy)^2+xy^3③x^2-10x+24先化简再求值:[(x+2y)(x-2y)-(x+4y)^2]÷4y,其中x=5,y=2

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初中因式分解!①(x^2-5)^2-16x^2②4yx^3+4(xy)^2+xy^3③x^2-10x+24先化简再求值:[(x+2y)(x-2y)-(x+4y)^2]÷4y,其中x=5,y=2初中因式

初中 因式分解!①(x^2-5)^2-16x^2②4yx^3+4(xy)^2+xy^3③x^2-10x+24先化简再求值:[(x+2y)(x-2y)-(x+4y)^2]÷4y,其中x=5,y=2
初中 因式分解!
①(x^2-5)^2-16x^2
②4yx^3+4(xy)^2+xy^3
③x^2-10x+24
先化简再求值:[(x+2y)(x-2y)-(x+4y)^2]÷4y,其中x=5,y=2

初中 因式分解!①(x^2-5)^2-16x^2②4yx^3+4(xy)^2+xy^3③x^2-10x+24先化简再求值:[(x+2y)(x-2y)-(x+4y)^2]÷4y,其中x=5,y=2
①(x^2-5)^2-16x^2
=(x^2-5-4x)(x^2-5+4x)
=(x-5)(x+1)(x-1)(x+5)
②4yx^3+4(xy)^2+xy^3
=xy(4x^2+4xy+y^2)
=xy(2x+y)^2
③x^2-10x+24
=(x-4)(x-6)
先化简再求值:[(x+2y)(x-2y)-(x+4y)^2]÷4y,其中x=5,y=2
[(x+2y)(x-2y)-(x+4y)^2]÷4y
=[x^2-4y^2-x^2-16y^2-8xy]÷4y
=(-12y^2-8xy)/(4y)
=-3y-2x
=-3*2-2*5
=-16

①原式=(x^2-5-4X)(x^2-5+4X)
=(x-5)(x+1)(x+5)(x-1)
②原式=xy[4x^2+4(xy)^2+y^2]
=xy(2x+y)^2
③原式=(x-4)(x-6)
原式等于(x^2-4y^2-x^2-8xy+16y^2)÷4y
=(12y^2-8xy)÷4y
=3y-2x
代入得-4

1.(X+1)*(X-1)*(X+5)*(X-5)