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2013-09-05T08:00:17-03:00
Primeiro as coisas básicas:

sec(x)=\frac{1}{cos(x)}
cossec(x)=\frac{1}{sen(x)}
cotg(x)=\frac{1}{tg(x)}=\frac{cos(x)}{sen(x)}


cossec(30)=\frac{1}{sen(30)}=\frac{1}{\frac{1}{2}}=2

cossec(120)=\frac{1}{sen(120)}=\frac{1}{sen(60)}=\frac{1}{\frac{\sqrt(3)}{2}}
=\frac{2}{\sqrt(3)}=\frac{2\sqrt(3)}{3}

cossec(270)=\frac{1}{sen(270)}=\frac{1}{- sen(90)}=\frac{1}{-1}=-1

cossec(135)=\frac{1}{sen(135)}=\frac{1}{sen(45)}=\frac{1}{\frac{\sqrt(2)}{2}}
=\frac{2}{\sqrt(2)}=\sqrt(2)

cossec(225)=\frac{1}{sen(225)}=\frac{1}{-sen(45)}=\frac{1}{-\frac{\sqrt(2)}{2}}
=-\frac{2}{\sqrt(2)}=-\sqrt(2)

cossec(300)=\frac{1}{sen(300)}=\frac{1}{-sen(60)}=\frac{1}{-\frac{\sqrt(3)}{2}}
=-\frac{2}{\sqrt(3)}=-\frac{2\sqrt(3)}{3}


cotg(\frac{\pi}{3})=\frac{cos(\frac{\pi}{3})}{sen(\frac{\pi}{3})}=\frac{\frac{1}{2}}{\frac{\sqrt{3}}{2}}
=\frac{1}{\sqrt{3}}=\frac{\sqrt{3}}{3}

sec(\frac{\pi}{3})=\frac{1}{cos(\frac{\pi}{3})}=\frac{1}{\frac{1}{2}}=2

cossec(\frac{\pi}{3})=\frac{1}{sen(\frac{\pi}{3})}=\frac{1}{\frac{\sqrt{3}}{2}}
=\frac{2}{\sqrt{3}}=\frac{2\sqrt{3}}{3}

sec(\frac{9\pi}{4})=\frac{1}{cos(\frac{9\pi}{4})}=\frac{1}{cos(\frac{\pi}{4})}
=\frac{1}{\frac{\sqrt{2}}{2}}=\frac{2}{\sqrt{2}}=\sqrt{2}


cotg(-1755)=\frac{cos(-1755)}{sen(-1755)}=\frac{cos(45)}{sen(45)}
=\frac{\frac{\sqrt{2}{2}}{\sqrt{2}{2}}=1


sec(1050)=\frac{1}{cos(1050)}=\frac{1}{cos(30)}=\frac{1}{\frac{\sqrt{3}}{2}}
=\frac{2}{\sqrt{3}}=\frac{2\sqrt{3}}{3}

cotg(-1410)=\frac{cos(-1410)}{sen(-1410)}=\frac{cos(30)}{sen(30)}
=\frac{\frac{\sqrt{3}}{2}}{\frac{1}{2}}=\sqrt{3}

Logo cotg(-1410) é maior.


x=180

y=\frac{5cosec(\frac{x}{2})-2sen(x)}{5sen(\frac{x}{2})}
y=\frac{5cosec(\frac{180}{2})-2sen(180)}{5sen(\frac{180}{2})}
y=\frac{5cosec(90)-2sen(180)}{5sen(90)}
y=\frac{5cosec(90)-0}{5}

FALTA ACABAR AQUI, MAS TENHO QUE SAIR, AJEITO ISSO ASSIM QUE VOLTAR.
POR FAVOR NÃO DELETEM.
2 5 2
y = cosec(90)
y = 1/sen(90)
y = 1/1
y = 1

Pronto, agora está completo