Question

найдите tg a если cos a = 5/12

Answer 1

1. $sin a = sqrt{1-frac{5^{2}}{12^{2}}}=$

 

$=sqrt{frac{144}{12^{2}}-frac{25}{12^{2}}}=$ 

 

$=sqrt{frac{144-25}{12^{2}}}=$ 

 

$=sqrt{frac{119}{12^{2}}}=$ 

 

$=frac{sqrt{119}}{12}}$ 

 

2. $tg a=frac{sin a}{cos a}=$ 

 

$tg a=frac{frac{sqrt{119}}{12}}{frac{5}{12}}=$ 

 

$tg a=frac{sqrt{119}}{5}$