Question

use os valores notáveis do seno e calcule :
d) sen 630°

Answer 1

$630^{\circ}=1\cdot 360^{\circ}+270^{\circ}$

$\mathrm{sen\,}630^{\circ}=\mathrm{sen}\left(270^{\circ}+1\cdot 360^{\circ} \right )\\ \\ \mathrm{sen\,}630^{\circ}=\mathrm{sen\,}270^{\circ}\\ \\ \boxed{\mathrm{sen\,}630^{\circ}=-1}$