![[Maple OLE 2.0 Object]](images/centr1.gif)
| > | #Формула Грина см. http://www.youtube.com/watch?feature=player_detailpage&v=LLpZ0jICaaw |
| > | restart; |
| > | x:=[1,1,7,1]: |
| > | y:=[1,4,1,1]: |
| > | printf("x y A x* y* Sx Sy"); |
| > | for i to 3 do |
| > | A[i]:=x[i+1]*y[i]-y[i+1]*x[i]; |
| > | Sx[i]:=(x[i+1]*y[i]-y[i+1]*x[i])*(y[i+1]+y[i]); |
| > | Sy[i]:=(x[i+1]*y[i]-y[i+1]*x[i])*(x[i+1]+x[i]); |
| > | printf("%a %a %a |%a %a %a %a \n",x[i],y[i],A[i],x[i]+x[i+1],y[i]+y[i+1],Sx[i],Sy[i]); |
| > |
| > | end: |
x y A x* y* Sx Sy
1 1 -3 |2 5 -15 -6
1 4 27 |8 5 135 216
7 1 -6 |8 2 -12 -48
| > | A_:=add(A[i],i=1..3)/2; |
| > | S_x:=add(Sx[i],i=1..3)/6; |
| > | S_y:=add(Sy[i],i=1..3)/6; |
| > | xc:=S_y/A_; |
| > | yc:=S_x/A_; |
| > |