Mathematics - Functions Question with Solution | TestHub

Clearly $f^1(0)$ is required $\left|f^1(0)\right|=\left|{\mathrm{lt}}_{n\to 0}\frac{f(h)}{h}\right|$

$={\mathrm{lt}}_{h\to 0}\frac{|f(h)|}{|h|}\le {\mathrm{lt}}_{h\to 0}\left|\frac{\tan \mathrm{h}}{h}\right|=1$