f(x) = x^n * x^{n + 1} = x^{2n + 1}
f'(x) = (2n + 1) * x^{2n}
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f(x) = x^{2n} / x = x^{2n - 1}
f'(x) = (2n - 1) * x^{2n - 2}
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f(x) = (x^n)^2 * x = x^{2n} * x = x^{2n + 1}
f'(x) = (2n + 1) * x^{2n}
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f(x) = (√x / x^n)^2 = x / x^{2n} = x^{1 - 2n}
f'(x) = (1 - 2n) * x^{-2n}