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3a²-2[2a²-(2ab-a²)+4ab]=()10+3(1+n²)-2(1-n+n²)+2(1-n+n²-n³)=()

题目详情
3a²-2[2a²-(2ab-a²)+4ab]=()
10+3(1+n²)-2(1-n+n²)+2(1-n+n²-n³)=()
▼优质解答
答案和解析
3a²-2[2a²-(2ab-a²)+4ab]
=3a²-4a²+4ab-2a²-8ab
=-3a²-4ab
10+3(1+n²)-2(1-n+n²)+2(1-n+n²-n³)
=10+3+3n²-2+2n-2n²+2-2n+2n²-2n³
=13+3n²-2n³