206k views
1 vote
Double-Angle and Half-Angle Identiies [See Attachment] Question3

Double-Angle and Half-Angle Identiies [See Attachment] Question3-example-1
User Eulerfx
by
7.6k points

1 Answer

2 votes

Seems to be a q and a theta here; presumably they're the same.



\sin \theta = - \frac 3 5



\cos \theta = + √( 1- \sin^2 \theta) = √(1- 9/25) = \frac 4 5


I chose the positive cosine because we're (almost) told
\theta is in the fourth quadrant.



\tan \theta = (\sin \theta)/(\cos \theta ) = (-3/5)/(4/5) = - \frac 3 4



\tan 2 \theta = (2 \tan \theta)/(1 - \tan^2 \theta) = (-3/2)/(1 - 9/16) = - (24)/(7)


Choice b




User Sgibbons
by
7.9k points