Question

Sendo cos x=3/5, com 0< x< π/2, calcule o valor de:
a)sen x
b)tg x
c)cos 2x
d)sen 2x
e)tg 2x​

Answer 1

Tarefa

Sendo cos x=3/5, com 0< x< π/2, calcule o valor de:

Explicação passo-a-passo:

sen^2(x) + cos^2(x) = 1

sen^2(x) = 25/25 - 9/25 = 16/25

a)sen x  = 4/5

b)tg x  = sen(x)/cos(x) = 4/3

c)cos 2x  = cos^2(x) - sen^2(x) = 9/25 - 16/25 = -7/25

d)sen 2x  = 2sen(x)*cos(x) = 2*4/5*3/5 = 24/25

e)tg 2x​ = -24/7