Question

Oblicz :

a) sin 120°

b) sin (-60°)

c) cos (-45°)

d) cos 750°

e) tg (-30°)

f) ctg 210°

Answer 1

Oblicz :

 

a) sin 120°= sin (180° -60°) = sin 60°= (1/2)*√3

b) sin (-60°)= - sin 60° = -( 1/2)*√3

c) cos (-45°)=  cos 45° = (1/2)*√2

d) cos 750°= cos (2*360° + 30°) = cos 30° = (1/2)*√3

e) tg (-30°)= - tg 30° = (1/3)*√3

f) ctg 210°= ctg( 180° + 30°) = ctg 30° = √3