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数学方程式简化1.(3x-4)(2x+7)2.(x^2-y)(x^2+y)(x^4+y^2)3.(a-1)(a^3-3a^2+3a-1)4.(2x^+3)(x-7)-(x+4)(x^2-1)

题目详情
数学方程式简化
1.(3x-4)(2x+7)
2.(x^2-y)(x^2+y)(x^4+y^2)
3.(a-1)(a^3-3a^2+3a-1)
4.(2x^+3)(x-7)-(x+4)(x^2-1)
▼优质解答
答案和解析
1.(3x-4)(2x+7)=6x^2+21x-8x-28=6x^2+13x-28
2.(x^2-y)(x^2+y)(x^4+y^2)=(x^4-y^2)(x^4+y^2)=x^8-y^2
3.(a-1)(a^3-3a^2+3a-1)
=a^4-3a^3+3a^2-a-a^3+3a^2-3a+1
=a^4-4a^3+6a^2-4a+1
4.(2x^+3)(x-7)-(x+4)(x^2-1)
=2x^3-14x^2+3x-21-(x^3-x+4x^2-4)
=x^3-18x^2+4x-17