Question

Given that cos 160= -q, express each of the following in terms of q:

a) cos 20
b) sin 160
c) tan(-20)
d) cos 70

Answer 1

Hello,

cos 160°=-q

cos 20°=-cos 160°=q

sin 20°=√(1-q²)=sin 160°

tan -20°=tan 160=√(1-q²)/-q

cos 70°=sin 20°=√(1-q²)