Re: [請益] 一題國中不等式數學
※ 引述《yts (noctilux f1.0 )》之銘言:
※ 引述《luuawa (窗邊的小荳荳)》之銘言:
: 1、設n為一整數,若n<1/100+1/101+1/102+1/103...+1/300<n+1,則n=?
: 我算出n=1
公式是不知道啦~
不過y =1/x
∫ydy=∫dx/x==============㏑300/100=㏑3=1......
從100~300
如果用看的是一下子就看出來了
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m大,絕對不是好運...
數學不該只有單一方法,本就因題而異
此題的巧合性很明顯,但若您所說的1/100+....+1/738以ln近似得到1.9....
^^^^^^^^^^^^^^^^^^
小弟相信大家都會質疑和猜忌是否要進位
任何近似都有盲點/死點(都可以舉出反例),要因題置疑才是數學思考 <--小弟如是淺見
小弟提供的是看到題目,爾後瞬間的看法,一如對數字的敏感度
若要正統教學,那還得依學生所習而有所區隔解題方法(這點大家也有相同看法吧@@)
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