作业帮三道分解因式的题目...
来源：学生作业帮 编辑：作业帮 分类：数学作业 时间：2024/07/17 17:19:39
三道分解因式的题目...
9(a-b)^2+12(a^2-b^2)+4(a+b)^2
=[9(a-b)^2+2*3*2(a+b)(a-b)+4(a+b)^2]
=[3(a-b)+2(a+b)]^2
=(5a-b)^2
下面的正好做 再答： (x^2-2x)^2+2x^2-4x+1
=(x^2-2x)^2+2(x^2-2x)+1
=(x^2-2x+1)^2
=(x-1)^4
49(x-y)^2-25(x+y)^2
=[7(x-y)+5(x+y)][7(x-y)-5(x+y)]
=(12x-2y)*(2x-12y)
=4(6x-y)(x-6y)
=[9(a-b)^2+2*3*2(a+b)(a-b)+4(a+b)^2]
=[3(a-b)+2(a+b)]^2
=(5a-b)^2
下面的正好做 再答： (x^2-2x)^2+2x^2-4x+1
=(x^2-2x)^2+2(x^2-2x)+1
=(x^2-2x+1)^2
=(x-1)^4
49(x-y)^2-25(x+y)^2
=[7(x-y)+5(x+y)][7(x-y)-5(x+y)]
=(12x-2y)*(2x-12y)
=4(6x-y)(x-6y)