%%
syms nn nb x
num = x^nb*(1-x)^(nn-nb);
denom = gamma(nn-nb+1)*gamma(nb+1)/gamma(nn+2);
p = num/denom;
p=x^nb*(1-x)^(nn-nb)/gamma(nn- nb+1)/gamma(nb+1)*gamma(nn+2);
figure(30)
ezplot(subs(p,[nn,nb],[35,15]),[0,1]);

%%