- #1
eleventhxhour
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8) Use each trigonometric ratio to determine all values of Θ, to the nearest degree if 0°≤ Θ ≤ 360°.
c) cosΘ = -0.8722
So, this is what I did for this question:
Θ=cos^-1(-0.8722)
Θ = 151°
This is correct, according to the textbook. However, it also gives another answer: 209°. How do you get this using the equations? (like sin (360° - Θ) = -sinΘ, tan (180° + Θ) = tanΘ, etc.)
d) cotΘ = 8.1516.
So, here's what I did for this part:
Θ = 7°
tan(180+7)= 187°
tan(360-7) = 353°
HOWEVER, the textbook only has the answers 7° and 187°. Why wouldn't 353° be correct?
Thanks!
c) cosΘ = -0.8722
So, this is what I did for this question:
Θ=cos^-1(-0.8722)
Θ = 151°
This is correct, according to the textbook. However, it also gives another answer: 209°. How do you get this using the equations? (like sin (360° - Θ) = -sinΘ, tan (180° + Θ) = tanΘ, etc.)
d) cotΘ = 8.1516.
So, here's what I did for this part:
Θ = 7°
tan(180+7)= 187°
tan(360-7) = 353°
HOWEVER, the textbook only has the answers 7° and 187°. Why wouldn't 353° be correct?
Thanks!