Asked by Cobra7710
Find all values of theta given that theta is between 0 degrees and 360 degrees. It is known that cos theta = -√3
____
2
____
2
Answers
Answered by
Ms. Sue
Timmy, Ryland, Cobra, Timmy -- you must be having an identity crisis tonight.
Please use the same name for all of your posts.
Please use the same name for all of your posts.
Answered by
Reiny
cosØ = -√3/2
1. find the reference angle
(using the positive result √3/2 , use inverse cos to get and angle of 30°
( Make yourself familiar with the ratio of sides of the 30-60-90 triangle)
2. Where is the angle Ø ?
Since the cosine is negative in II and III
in II : Ø = 180-30 or 150°
or
in III : Ø = 180+30 = 210°
1. find the reference angle
(using the positive result √3/2 , use inverse cos to get and angle of 30°
( Make yourself familiar with the ratio of sides of the 30-60-90 triangle)
2. Where is the angle Ø ?
Since the cosine is negative in II and III
in II : Ø = 180-30 or 150°
or
in III : Ø = 180+30 = 210°
Answered by
Cobra7710
oh so we only want reference angle. i thought values meant sin,cos,and tan. how do you know it only wanted reference angle?
Answered by
Reiny
didn't it say,
"Find the values of Ø" , <b>not</b> find the values of sinØ etc ?
Finding the reference angle is only the first step, from there you have to decide what to do with that reference angle depending on the position of Ø and the values of cosØ
"Find the values of Ø" , <b>not</b> find the values of sinØ etc ?
Finding the reference angle is only the first step, from there you have to decide what to do with that reference angle depending on the position of Ø and the values of cosØ