八年级上册数学第十四章（整式乘法与因式分解）单元测试题
整式的乘除与因式分解单元测试卷 因式分解同步练习（解答题）解答题 9．把下列各式分解因式：①a2+10a+25 ②m2-12mn+36n2 ③xy3-2x2y2+x3y ④（x2+4y2）2-16x2y2 10．已知x=-19，y=12，求代数式4x2+12xy+9。
因式分解练习题及答案 你可真狠 要这么多题目1.5ax+5bx+3ay+3by解法：=5x(a+b)+3y(a+b)(5x+3y)(a+b)2.x^3-x^2+x-1解法：=(x^3-x^2)+(x-1)x^2(x-1)+(x-1)(x-1)(x^2+1)3.x2-x-y2-y解法：=(x2-y2)-(x+y)(x+y)(x-y)-(x+y)(x+y)(x-y-1)bc(b+c)+ca(c-a)-ab(a+b)bc(c-a+a+b)+ca(c-a)-ab(a+b)bc(c-a)+bc(a+b)+ca(c-a)-ab(a+b)bc(c-a)+ca(c-a)+bc(a+b)-ab(a+b)(bc+ca)(c-a)+(bc-ab)(a+b)c(c-a)(b+a)+b(a+b)(c-a)(c+b)(c-a)(a+b)．x^2+3x-40x^2+3x+2.25-42.25(x+1.5)^2-(6.5)^2(x+8)(x-5)．(x^2+x+1)(x^2+x+2)-12时，可以令y=x^2+x，则原式=(y+1)(y+2)-12y^2+3y+2-12=y^2+3y-10(y+5)(y-2)(x^2+x+5)(x^2+x-2)(x^2+x+5)(x+2)(x-1)．(1+y)^2-2x^2(1+y^2)+x^4(1-y)^2原式=(1+y)^2+2(1+y)x^2(1+y)+x^4(1-y)^2-2(1+y)x^2(1-y)-2x^2(1+y^2)[(1+y)+x^2(1-y)]^2-2(1+y)x^2(1-y)-2x^2(1+y^2)[(1+y)+x^2(1-y)]^2-(2x)^2[(1+y)+x^2(1-y)+2x]·[(1+y)+x^2(1-y)-2x](x^2-x^2y+2x+y+1)(x^2-x^2y-2x+y+1)[(x+1)^2-y(x^2-1)][(x-1)^2-y(x^2-1)](x+1)(x+1-xy+y)(x-1)(x-1-xy-y)x^5+3x^4y-5x^3y^2+4xy^4+12y^5原式=(x^5+3x^4y)-(5x^3y^2+15x^2y^3)+(4xy^4+12y^5)x^4(x+3y)-5x^2y^2(x+3y)+4y。
