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The maximum value of x−xx^{-x} is

Solution

✅ Correct Option: 2

Let f(x)=x−xf(x) = x^{-x}. Taking logarithm: ln⁡f(x)=−xln⁡x\ln f(x) = -x \ln x. Differentiating: f′(x)f(x)=−(1+ln⁡x)\frac{f'(x)}{f(x)} = -(1+\ln x). Setting f′(x)=0f'(x) = 0: 1+ln⁡x=0⇒x=1/e1 + \ln x = 0 \Rightarrow x = 1/e. Maximum value =(1/e)−1/e=e1/e= (1/e)^{-1/e} = e^{1/e}.

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