Deffun("f(x)",["regional(y)","y=exp(x)","y"]);
Plotdata("1","f(x)","x");
／／ 関数y=f(x)のグラフを描く．
Putpoint("A",[0,f(0)]);
coeff=Derivative("f(x)","x",A.x);
／／ 点Aにおける接線の傾きを求める．
Defvar("Coeff=coeff");
Deffun("g(x)",["regional(y)","y=Coeff*(x-A.x)+A.y","y"]);
Setcolor([0,0,1]);
Plotdata("2","g(x)","x");
／／ 点Aにおける接線を色を指定して描く．
Setpen(0.5);
Listplot("1",
0,1],[1,1],[1,2],[0,2);
／／ 線分を描く．
Putpoint("B",[1,1]);
Putpoint("C",[1,2]);
Bowdata([B,C],[1.5,0.4,"Expr=\color{black}1"]);
／／ 弓形を描く．
Setpen(1);
Listplot("2",
0,f(1)],[1,f(1)],[1,g(1),["do"]);
Listplot("3",
1,0],[1,1,["do"]);
／／ 点線を描く．
Setcolor([0,0,0]);
Htickmark([1,"s","1"]);
Vtickmark([1,"nw","1",2,"w","2",f(1),"w","e",3,"w","3"]);
Expr([[log(3.5),3.5],"n","y=e^x"]);
