When the computer puts in arctan(-1)+ 3.14 is 2.356 but this calculator gets 2.379. How is that?
+118723 $$\left({\frac{{\mathtt{\pi}}}{{\mathtt{180}}}}\right){\mathtt{\,\times\,}}\underset{\,\,\,\,^{\textcolor[rgb]{0.66,0.66,0.66}{360^\circ}}}{{tan}}^{\!\!\mathtt{-1}}{\left(-{\mathtt{1}}\right)}{\mathtt{\,\small\textbf+\,}}{\mathtt{3.14}} = {\mathtt{2.354\: \!601\: \!836\: \!602\: \!551\: \!7}}$$
$$\left({\frac{{\mathtt{\pi}}}{{\mathtt{180}}}}\right){\mathtt{\,\times\,}}\underset{\,\,\,\,^{\textcolor[rgb]{0.66,0.66,0.66}{360^\circ}}}{{tan}}^{\!\!\mathtt{-1}}{\left(-{\mathtt{1}}\right)}{\mathtt{\,\small\textbf+\,}}{\mathtt{\pi}} = {\mathtt{2.356\: \!194\: \!490\: \!192\: \!344\: \!9}}$$
i used this calc and i get 2.356
--------------------------
now without a calc
atan(-1)+pi = -pi/4 + pi = 3pi/4
$${\frac{{\mathtt{3}}{\mathtt{\,\times\,}}{\mathtt{\pi}}}{{\mathtt{4}}}} = {\mathtt{2.356\: \!194\: \!490\: \!192\: \!344\: \!9}}$$
+118723 $$\left({\frac{{\mathtt{\pi}}}{{\mathtt{180}}}}\right){\mathtt{\,\times\,}}\underset{\,\,\,\,^{\textcolor[rgb]{0.66,0.66,0.66}{360^\circ}}}{{tan}}^{\!\!\mathtt{-1}}{\left(-{\mathtt{1}}\right)}{\mathtt{\,\small\textbf+\,}}{\mathtt{3.14}} = {\mathtt{2.354\: \!601\: \!836\: \!602\: \!551\: \!7}}$$
$$\left({\frac{{\mathtt{\pi}}}{{\mathtt{180}}}}\right){\mathtt{\,\times\,}}\underset{\,\,\,\,^{\textcolor[rgb]{0.66,0.66,0.66}{360^\circ}}}{{tan}}^{\!\!\mathtt{-1}}{\left(-{\mathtt{1}}\right)}{\mathtt{\,\small\textbf+\,}}{\mathtt{\pi}} = {\mathtt{2.356\: \!194\: \!490\: \!192\: \!344\: \!9}}$$
i used this calc and i get 2.356
--------------------------
now without a calc
atan(-1)+pi = -pi/4 + pi = 3pi/4
$${\frac{{\mathtt{3}}{\mathtt{\,\times\,}}{\mathtt{\pi}}}{{\mathtt{4}}}} = {\mathtt{2.356\: \!194\: \!490\: \!192\: \!344\: \!9}}$$
