Use a half-angle identity to find the exact value of tan 157.5Β°.
Accepted Solution
A:
Use the half angle identity, tan157.5=(1-cos315)/sin315 cos315=cos(-45)=β2/2, sin315=-β2/2 tan157.5=(1-β2/2)/(-β2/2)=(2-β2)/(-β2)=(2β2-2)/(-2)=1-β2