This answer partially references GPT, GPT_Pro to solve the problem better
Proof: If f(x)g(x) is not all zero, then at least one of f(x) or g(x) is not zero.
Let f(x)=a_nx^n+a_(n-1)x^(n-1)+... +a_0,g(x)=b_mx^m+b_(m-1)x^(m-1)+... Plus b_0.
According to the formula:
(f(x)g(x)) ^n=(a_nx^n+a_(n-1)x^(n-1)+... +a_0)(b_mx^m+b_(m-1)x^(m-1)+... +b_0)^n
=a_n^nb_m^nx^{mn}+(a_nb_m^{n-1}+a_{n-1}b_m^n)x^{mn-1}+(a_nb_{m-1}^{n-1}+a_{n-1}b_{m-1}^{n-2}+... +a_0b_m^n)x^{mn-2}+... +(a_{n-1}b_0^{n-2}+a_0b_0^{n-1})x^{m+n-2}+a_0b_0^{n}x^{m+n-1}
and(f(x), g(x)) ^ n = a_nb_mx ^ {}(m + n) - 1 +(a_(n - 1} b_} {m - 1) x ^ {2} m + n - +(a_ b_ {n - 2} {2} m -) x ^ {3} m + n - +... +(a_0b_0)x^{m+n-(m+1)}
It follows that
When f(x) or g(x) is not zero, the coefficients of the above two formulas are the same, it can be proved.
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