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Question
If f(x) attains a local minimum at x = c, then write the values of `f' (c)` and `f'' (c)`.
Solution
If f(x) attains a local minimum at x = c, then the first order derivative of the function at the given point must be equal to zero, i.e.
`f'(x) = 0" at "x = c`
`f''(c) > 0`
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