Question

cos 390
tg 210
sin 405
cos300

Answer 1

cos 390=0,903
tg 210=-0,529
sin 405= 0,262
cos 300=-0,022

Answer 2

Cos 390=Cos(360+30)=Cos30=√3/2
tg 210=tg(180+30)=tg30=√3/3
sin 405=sin(360+45)=sin 45=√2/2
cos300=cos(360-60)=cos60=1/2