Area in a function

Im trying to fill the area under a function but I dont know how to exactly do it, I want to plot the area between [-1, 1]

syms f(x)
f=1-x^4

f = 

t=0

t = 0

I=int(f)

I = 

Area=subs(I,1)-subs(I,-1)

Area = 

fplot(f,[-1,1])
hold on 
fplot(t,'b')

Answer 1

[David Hill]

x=-1:.001:1;
f=1-x.^4;
g=zeros(size(x));
plot(x,g,x,f);
x2 = [x, fliplr(x)];
inBetween = [g, fliplr(f)];
fill(x2, inBetween, 'g');