Need urgent help with this problem.

1)Let f be a function in C0[0,1] ie the space of continuous functions defined on the unit interval. Suppose that the Integral from 0 to 1 of the product of f and g (ie, f(x)*g(x) integrated from 0 to 1), for any g in C0[0,1] always vanishes. Prove that F is the constant zero function on [0,1].

2) What if g is restricted to being of the form g(x)=x^n for some natural n?

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