Let S be the set of all functions ƒ : [0,1] $\to$ R, which are continuous on [0,1] and differentiable on (0,1). Then for every ƒ in S, there exists a c $\in$ (0,1), depending on ƒ, such that
Solution
<p>If we consider the case where f(x) is a constant function, then its derivative f'(x) is equal to 0 for all x in the interval (0,1). </p>
<p>Therefore, if we substitute this into the expressions provided in Options A, B and C, we would have :</p>
<p>Option A : |f(c) - f(1)| < |f'(c)| would become |constant - constant| < |0|, which is 0 < 0. This is not true.</p>
<p>Option B : |f(c) + f(1)| < (1 + c)|f'(c)| would become |constant + constant| < (1 + c)$\times$0, which is a positive number < 0. This is not true.</p>
<p>Option C : |f(c) - f(1)| < (1 - c)|f'(c)| would become |constant - constant| < (1 - c)$\times$0, which is 0 < 0. This is not true.</p>
<p>Hence, for the case where f(x) is a constant function, none of the options A, B and C are correct.</p>
<p>So, the correct answer would be Option D : None.</p>
About this question
Subject: Mathematics · Chapter: Limits, Continuity and Differentiability · Topic: Limits and Standard Results
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