How to fill region between two graphs using different styles or patterns?

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Are you looking for something like this:

f(x) = -1/8*x^3+x
g(x) = 1/2*x
h(x) = 1/4*x^2
plot([f,g,h],-2,3,fill={0:g,1:h,2:0})

For more details, you should go to the plotting documentation and search for "fill " - in particular, you can even fill between different functions using the function itself as the key value. And example from there:

sage: plot(1.13*log(x), 1, 100, fill = lambda x: nth_prime(x)/floor(x), fillcolor = 'red')