[tex]\displaystyle \text{Acompanhe.}\\\\ 2)\\ a) \,\, \sin \alpha=\frac{B}{A}, \,\, \cos \alpha=\frac{C}{A}, \,\, \tan \alpha=\frac{B}{C}.\\\\ b) \,\, \sin \beta=\frac{x}{z}, \,\, \cos \beta=\frac{y}{z}, \,\, \tan \beta=\frac{x}{y}.\\\\ 3) \,\, \text{Alguns valores importantes para este exerc\'icio s\~ao: }\\\\ a_1) \,\, \sin 30^{\circ}=\frac{1}{2}\\\\ a_2) \,\, \cos 30^{\circ}=\frac{\sqrt{3}}{2}\\\\ a_3) \,\, \tan 30^{\circ}=\frac{1}{\sqrt{3}}[/tex]
[tex]\displaystyle \\\\ b_1) \,\, \sin 45^{\circ}=\frac{1}{\sqrt{2}}\\\\ b_2) \,\, \cos 45^{\circ}=\frac{1}{\sqrt{2}}\\\\ b_3) \,\, \tan 45^{\circ}=1\\\\ \text{Agora, dada esta explica\c c\~ao e alguns valores trigonom\'etricos,}\\\\ \text{voc\^e est\'a apto para realizar o exerc\'icio 3). Caso tenha d\'uvidas,}\\\\ \text{pergunte a sua d\'uvida. Se voc\^e n\~ao tentar, voc\^e n\~ao aprende.}\\\\ \text{Bons estudos ma dear.}[/tex]
