4楼: Originally posted by Mr__Right at 2016-03-12 12:52:47
后面漏掉一个 “]", 然后Shift+Enter...

f[x_]:=NIntegrate[(Tanh[t]-Tanh[x])/(x^2-t^2),{t,0,Infinity}];Plot[f[x],{x,0,50},
AxesOrigin->{0,-.1},PlotStyle->Red],ImageSize->700,AxesStyle->{{Directive[Black, 18],Arrowheads[.035],Thick},{Directive[Black, 18],Arrowheads[.035],Thick}}

2楼: Originally posted by Mr__Right at 2016-03-12 09:58:12
这类情况用Mathematica似乎更合适。



f:=NIntegrate;Plot,ImageSize->700,AxesStyle->{{Directive,Arrowheads,Thick},{Directive,Arrowheads,Thick}}
...

3楼: Originally posted by xiao-niao- at 2016-03-12 12:45:43
好厉害，可是为什么我把你的代码复制进mathamatica，不画图呢...