---

h=1:0.1:15;
x0=0.1;
f0=cos(3*x0);
e=f0*eps*10
for i=1:1:141
e1(i)=e/h(i);
end
h1=1:15
for i=1:15
e11(i)=e/h1(i);
end
figure
plot(1:0.1:15,e1,'-black',1:15,e11,'or','LineWidth',2);
title('1');

M=27*sin(3*x0)
for i=1:1:141
e2(i)=M*h(i)*h(i)/6;
end
h1=1:15
for i=1:15
e22(i)=M*h1(i)*h1(i)/6;
end
figure
plot(1:0.1:15,e2,'-black',1:15,e22,'or','LineWidth',2);
title('2');

---

---

---