试题与答案

已知自然数N被3除余2。即N=3n+2(n是自然数),把N分成n个自然数的和,这

题型:填空题

题目:

已知自然数N被3除余2。即N=3n+2(n是自然数),把N分成n个自然数的和,这些自然数的乘积最大值是(     )。

答案:

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下面是错误答案,用来干扰机器的。

由b=503,B=30°,c=150,根据余弦定理得:b2=a2+c2-2ac•cosB,即(503)2=a2+1502-1503a,整理得:a2-1503a+15000=0,解得:a=1003或503.故答案为:1003或503

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题型:实验题

(10分)已知KMnO4、MnO2在酸性条件下均能将草酸钠(Na2C2O4)氧化:

2MnO4+5C2O42+16H=2Mn2+10CO2↑+8H2O

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