[tex]\large\boxed{\begin{array}{l}\underline{\sf relac_{\!\!,}\tilde ao\,entre\,radiano\,e\,grau}\\\rm 1\,rad\approxeq57,29^\circ\\\\\sf c)~\rm 1\,rad\longrightarrow 57,29^\circ\\\rm 4\,rad\longrightarrow x\\\rm x=4\cdot57,29^\circ\\\rm x=229,16^\circ\longrightarrrow pertence\,ao\,3^o~quadrante\\\rm portanto\, tg(4)\,\acute e\,positivo\end{array}}[/tex]
[tex]\large\boxed{\begin{array}{l}\sf d)~\rm 1\,rad\longrightarrow 57,29^\circ\\\rm 2\,rad\longrightarrow y\\\rm y=2\cdot57,29^\circ\\\rm y=114,58^\circ\,pertence\,ao\,2^o\,quadrante\\\rm portanto\,tg(2)\,\acute e\,negativo\end{array}}[/tex]
[tex]\large\boxed{\begin{array}{l}\sf e)~\rm 1\,rad\approxeq57,29^\circ\\\rm portanto\,tg(1)\,\acute e\,positivo.\\\rm\underline{resumo\,da\,\acute opera\!:}\\\sf para\,achar\,os\,sinais,converte-se\,radiano\,em\,grau\\\sf usando\,a\,informac_{\!\!,}\tilde ao\,1\,rad\approxeq57,29^\circ\\\sf uma\,vez\,transformado\,em\,grau\,fica\,f\acute acil\\\sf saber\,o\,quadrante\,e\,por\,consequ\hat encia\,o\,sinal.\end{array}}[/tex]
