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1.(x^2-3)^2+2(x^2-3)(x-3)+(x-3)^22.(x+1)(x+3)(x+5)(x+7)+153.x^2+y^2+4x+2y+34.(a^2+a+1)^2+2(a^2+a+1)(a^2+a-1)+(a^2+a-1)^25.(x^2+4)^2-16x^2

题目详情
1.(x^2-3)^2+2(x^2-3)(x-3)+(x-3)^2
2.(x+1)(x+3)(x+5)(x+7)+15
3.x^2+y^2+4x+2y+3
4.(a^2+a+1)^2+2(a^2+a+1)(a^2+a-1)+(a^2+a-1)^2
5.(x^2+4)^2-16x^2
▼优质解答
答案和解析
1.原式=(x^2-3+x-3)^2=(x^2+x-6)^2=(x+3)^2(x-2)^2
2.原式=[(x+1)(x+7)][(x+3)(x+5)]+15
=(x^2+8x+7)(x^2+8x+15)+15
=(x^2+8x)^2+22(x^2+8x)+105+15
=(x^2+8x)^2+22(x^2+8x)+120
=(x^2+8x+12)(x^2+8x+10)
=(x+2)(x+6)(x^2+8x+10)
3.这道有问题,不能分解
4.原式=(a^2+a+1+a^2+a-1)^2
=(2a^2+2a)^2=4a^2(a+1)^2
5.原式=(x^2+4+4x)(x^2+4-4x)=(x+2)^2(x-2)^2