Determine Coterminal Angles

[nycmathguy]

Section 4.1

Let C_A = angles coterminal with angle A.

C_A = B & C

You say?

 

[MathLover1]

first one example:
Since the terminal side of a 50° angle resides in quadrant I, the terminal side of its coterminal angle must share that side. This means the new angle would make one complete revolution before having its
terminal side come to rest at the same place.
Therefore, to find the coterminal angle to a 50° angle, just add 360°.

50° + 360° = 410°

compare your angle A and find coterminal

 

[nycmathguy]

first one example:
Since the terminal side of a 50° angle resides in quadrant I, the terminal side of its coterminal angle must share that side. This means the new angle would make one complete revolution before having its
terminal side come to rest at the same place.
Therefore, to find the coterminal angle to a 50° angle, just add 360°.

50° + 360° = 410°
View attachment 873

compare your angle A and find coterminal

Angle A is not given to be 50 degrees. The question is asking for coterminal angles amomg the ones given in the picture. I see that angles B and C also end in quadrant 1. No?

 

[nycmathguy]

first one example:
Since the terminal side of a 50° angle resides in quadrant I, the terminal side of its coterminal angle must share that side. This means the new angle would make one complete revolution before having its
terminal side come to rest at the same place.
Therefore, to find the coterminal angle to a 50° angle, just add 360°.

50° + 360° = 410°
View attachment 873

compare your angle A and find coterminal

Question

Is the following course nonEucledian Geometry? By the way, this professor is horrible, just plain horrible.
Take a look when time allows.

Advanced Geometry Course

 

[MathLover1]

agree, professor is horrible

try this one, it is much better

 

[MathLover1]

Angle A is not given to be 50 degrees. The question is asking for coterminal angles amomg the ones given in the picture. I see that angles B and C also end in quadrant 1. No?

I know that Angle A is not given to be 50 degrees, that was just an example to get an idea how to do it

 

[nycmathguy]

I know that Angle A is not given to be 50 degrees, that was just an example to get an idea how to do it

Question:

Why is my answer wrong? Angles B and C also end up on the ray whose vertex is the origin for the angle A counterclockwise rotation. No?

 

[MathLover1]

you need to add 360 degrees to angle A
and, angle coterminal with angle A is only Angle B

 

[nycmathguy]

you need to add 360 degrees to angle A
and, angle coterminal with angle A is only Angle B

Angle B rotates in the same direction as angle A. In fact, angle B ends up on the same ray in quadrant 1. Interesting section so far. One of my favorite sections is coming soon. That is, right triangle trigonometry.