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1.x^4+3x²y²+4y^4 2.x^4+4 3.x²-2x-a²+2a 4.(x+y)²-4x-4y+41.x^4+3x²y²+4y^4 2.x^4+4 3.x²-2x-a²+2a 4.(x+y)²-4x-4y+4 5.x(x-2)-a(a-2) 6.(x+y)²-4(x+y-1)

题目详情
1.x^4+3x²y²+4y^4 2.x^4+4 3.x²-2x-a²+2a 4.(x+y)²-4x-4y+4
1.x^4+3x²y²+4y^4 2.x^4+4 3.x²-2x-a²+2a 4.(x+y)²-4x-4y+4 5.x(x-2)-a(a-2) 6.(x+y)²-4(x+y-1)
▼优质解答
答案和解析
1.x^4+3x²y²+4y^4
=x^4+4x²y²+4y^4-x²y²
=(x^2+2y^2)^2-x²y²
=(x^2+2y^2-xy)(x^2+2y^2+xy)
2.x^4+4
=x^4+4x^2+4-4x^2
=(x^2+2)^2-4x^2
=(x^2+2-2x)(x^2+2+2x)
3.x²-2x-a²+2a
=x²-a²-2x+2a
=(x-a)(x+a)-2(x-a)
=(x-a)(x+a-2)
4.(x+y)²-4x-4y+4
=(x+y)²-4(x+y)+4
=(x+y-2)²
5.x(x-2)-a(a-2)
=x²-2x-a²+2a
=x²-a²-2x+2a
=(x-a)(x+a)-2(x-a)
=(x-a)(x+a-2)
6.(x+y)²-4(x+y-1)
=(x+y)²-4(x+y)+4
=(x+y-2)²