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计算:999的三次方+3乘999的平方+3乘999+1
人气:488 ℃ 时间:2019-10-19 17:15:04
解答
令a=999
则原式=a³+3a²+3a+1
=a³+a²+2a²+3a+1
=a²(a+1)+(2a+1)(a+1)
=(a+1)(a²+2a+1)
=(a+1)³
=1000³
=1000000000
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