CÔNG THỨC SIMPSON TÍNH TÍCH PHÂN
Code:
(*Cong thuc Simpson*)
Clear[x, y, f, a, b, n, h, x, fx];
y = Input["Nhap f(x)"];
f[x_] = y;
a = Input["Nhap a"];
b = Input["Nhap b"];
Print["f(x) = ", y];
Print["a = ", a];
Print["b = ", b];
(*Cau a : Tich tich phan*)
Print["---- Cau a ----"];
Print["I= ", Integrate[y, {x, a, b}]];
(*Cau b : Cong thuc Simpson*)
Print["---- Cau b ----"];
n = Input["Nhap n"];
h = (b - a)/(2n);
x = Table[a + i*h, {i, 0, 2n}];
fx = Table[f[x[[i]]], {i, 1, 2n + 1}];
Simpson = (h/3)*(fx[[1]] + fx[[2n + 1]] + 4Sum[fx[[i]], {i, 2, 2n, 2}] + 2Sum[fx[[i]], {i, 3, 2n - 1, 2}]);
Print["Cong thuc Simpson I = ", Simpson];
(*Cau c : Ve do thi*)
Print["---- Cau c ----"];
Plot[y, {x, a, b}];