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一、计算题1.(x+y)(x-y)^22.(a-2b+3)(a+2b-3c)3.[(x+2y)(x-2y)-(x-2y)^2+8y(x+y)]^2÷4x4.解方程(x+3)(2x-5)-(2x+1)(x-8)=415.先化简再求值(x-2)(x-3)+2(x+6)(x-5)-3(x^2-7x+13)其中x=-1

题目详情
一、计算题
1.(x+y)(x-y)^2
2.(a-2b+3)(a+2b-3c)
3.[(x+2y)(x-2y)-(x-2y)^2+8y(x+y)]^2÷4x
4.解方程(x+3)(2x-5)-(2x+1)(x-8)=41
5.先化简再求值(x-2)(x-3)+2(x+6)(x-5)-3(x^2-7x+13)
其中x=-1
▼优质解答
答案和解析
1.(x+y)(x-y)^2 =(x^2-y^2)(x-y)=x^3-x^2y-xy^2+y^32.(a-2b+3c)(a+2b-3c) =a^2-(2b-3c)^2=a^2-4b^2+12bc-9c^23.[(x+2y)(x-2y)-(x-2y)^2+8y(x+y)]^2÷4x =[(x-2y)(x+2y-x+2y)+8y(x+y)]^2÷4x =[4y(x-2y)+8y(x...