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Let f(x) = x^2 + bx + 7. If f'(5) = 2f'(...

Let `f(x) = x^2 + bx + 7`. If f'(5) = 2f'`(7/2)`, then the value of 'b' is

A

4

B

3

C

`-4`

D

`-3`

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MODERN PUBLICATION-CONTINUITY AND DIFFERENTIABILITY-EXERCISE
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