Derivative confusion

$x\in \Re$ $\\ f\left( x \right) =x+x+x+......x\quad \quad (x\quad times)\\$ $Then\quad first\quad derivative\quad of\quad f\left( x \right) \quad will\quad be\quad x\quad or\quad 2x?$ The confusion arrived due to a problem similar to it.

Easy Math Editor

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