Proving a function satisfies a functional equation

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Does \(f(x) = \sqrt{x}\) satisfy \(f(x - y) = \dfrac{f(x)}{f(y)}?\) If so, prove it.
Does \(f(x) = \dfrac{1}{x^2}\) satisfy \(f(xy) = f(x)f(y)?\) If so, prove it.