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因式分解:x3-11x2+31x-21

题目详情
因式分解:x3-11x2+31x-21
▼优质解答
答案和解析
x³-11x²+31x-21
=(x³-x²)-(10x²-10x)+(21x-21)
=x²(x-1)-10x(x-1)+21(x-1)
=(x²-10x+21)(x-1)
=(x-3)(x-7)(x-1)
=(x-1)(x-3)(x-7)