format long
s=quadgk(@(x)  (12*x.^2+1)./((0.85-x).*(1-0.8*x).^2 .*(11*x+1).^2 ),0.2,0.6)

s =

   0.234855895637609

syms x
ss=int((12*x^2+1)/((0.85-x)* (1-0.8*x)^2 *(11*x+1)^2 ),0.2,0.6);
s=vpa(ss,6)

s =

0.234856

2楼: Originally posted by 月只蓝 at 2016-05-25 09:45:45
format long
s=quadgk(@(x)  (12*x.^2+1)./((0.85-x).*(1-0.8*x).^2 .*(11*x+1).^2 ),0.2,0.6)

s =

   0.234855895637609


或者：


syms x
ss=int((12*x^2+1)/((0.85-x)* (1-0.8*x)^2 *(11*x+1 ...