Pochodna funkcji arctanx

$f\left(x\right) =$	$\arctan\left(x\right)$
$\dfrac{\mathrm{d}\left(f\left(x\right)\right)}{\mathrm{d}x} =$	$\class{steps-node}{\cssId{steps-node-1}{\tfrac{\mathbf{d}}{\mathbf{d}\boldsymbol{x}}\kern-.25em\left(\arctan\left(x\right)\right)}}$ $=\class{steps-node}{\cssId{steps-node-2}{\dfrac{1}{{x}^{2}+1}}}$

$f\left(x\right) =$

$\arctan\left(x\right)$

$\dfrac{\mathrm{d}\left(f\left(x\right)\right)}{\mathrm{d}x} =$

$\class{steps-node}{\cssId{steps-node-1}{\tfrac{\mathbf{d}}{\mathbf{d}\boldsymbol{x}}\kern-.25em\left(\arctan\left(x\right)\right)}}$

$=\class{steps-node}{\cssId{steps-node-2}{\dfrac{1}{{x}^{2}+1}}}$