Question

Calculati cos35 - sin55
 

Answer 1

Vom folosi formula cosx=sin(90°-x) si vom obtine:

cos35°=sin(90°-35°)=sin55°

Atunci, exercitiul devine:

cos35°-sin55°=sin55°-sin55°=0.

Answer 2

$\it cos35^o=sin(90^o-35^o)= sin55^o$

Expresia din enunț devine:

$\it sin55^o-sin55^o = 0$