Let $f(x)=\frac{20}{x^{2}+1}$.
Enter an antiderivative of $f(x)$

Step 1 ：Let \(f(x)=\frac{20}{x^{2}+1}\).

Step 2 ：The question is asking for an antiderivative of the function \(f(x)=\frac{20}{x^{2}+1}\). An antiderivative of a function is a function whose derivative is the original function. In other words, we need to find a function F(x) such that F'(x) = f(x).

Step 3 ：The function \(f(x)=\frac{20}{x^{2}+1}\) is a standard form of a function whose antiderivative is known. The antiderivative of \(\frac{1}{x^{2}+1}\) is \(arctan(x)\), so the antiderivative of \(\frac{20}{x^{2}+1}\) is \(20*arctan(x)\).

Step 4 ：Final Answer: The antiderivative of \(f(x)=\frac{20}{x^{2}+1}\) is \(\boxed{20*arctan(x)}\).