Question

Considerando 0 < a < 90° calcule sen a, cos a e sec a, sendo tan a=5/4

Answer 1

tg²a +1 = senc² a
(5/4)² + 1 = sec² a
25/16 +1 = senc² a
Senc² a = raiz de 41/raiz 16
Senc² a = raiz 41/4
Senc a = 1,21

senc a = 1/cos a
cos a = 1/senc a
cos a = 0,826

Sen² a + cos² a = 1
Sen² a + (0,826)² = 1
sen² a = 0,317724
sen a = aprox. 0,0567