几道因式分解1.ab(c²-d²)+cd(a²-b²)2.x²-4mx+8mn-4n²3.x4+644.x³-11x²+31x-215.x³-4xy²-2x²y+8y³但别太繁琐
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几道因式分解1.ab(c²-d²)+cd(a²-b²)2.x²-4mx+8mn-4n²3.x4+644.x³-11x²+31x-215.x³-4xy²-2x²y+8y³但别太繁琐
几道因式分解
1.ab(c²-d²)+cd(a²-b²)
2.x²-4mx+8mn-4n²
3.x4+64
4.x³-11x²+31x-21
5.x³-4xy²-2x²y+8y³
但别太繁琐
几道因式分解1.ab(c²-d²)+cd(a²-b²)2.x²-4mx+8mn-4n²3.x4+644.x³-11x²+31x-215.x³-4xy²-2x²y+8y³但别太繁琐
1.ab(c²-d²)+cd(a²-b²)
=abc²-abd²+a²cd-b²cd
=(abc²+a²cd)-(abd²+b²cd)
=ac(bc+ad)-bd(ad+bc)
=(ac-bd)(bc+ad)
2.x²-4mx+8mn-4n²
=x²-4mx+4m²-4m²+8mn-4n²
=(x²-4mx+4m²)-(4m²-8mn+4n²)
=(x-2m)²-(2m-2n)²
=(x-2n)(x-4m+2n) (平方差公式)
3.x^4+64
=(x^4+64+16x²)-16x²
=(x²+8)²-(4x)²
=(x²+4x+8)(x²-4x+8) (平方差公式)
4.x³-11x²+31x-21
=(x-1)(x²-10x+21)
=(x-1)(x-3)(x-7)
5.x³-4xy²-2x²y+8y³
=(x-2y)(x²-4y²)
=(x-2y)²(x+2y)
1.(ac-bd)(ad+bc)
2.(x-2n)(x-4m+2n)
3.(x+2)(x^3-2x^2+4x-8)
4.(x-1)(x-3)(x-7)
5.(x-4y)(x^2-2y^2)(有理数范围内)