Pi/3 is the reference angle for: a. 2pi/3 b. 15pi/3 c. 7pi/3 d. 19pi/3 **its choose all that ! : ) my answers: c. 7pi/3 and d. 19pi/3 are those right? ?

yes those are right but 2pi/3 is also right.

Step-by-step explanation:

The correct answers are A,C and D

Step-by-step explanation:

Given an angle θ, we call the reference angle for θ as '' θ ref ''.

Using the x-axis as our frame of reference, θ ref is always the smallest angle that you can make from the terminal side of an angle with the x-axis.

Let's note the quadrants of the IR2 as Q.

For an angle θ in QI, θ ref = θ

For an angle θ in QII, θ ref = π - θ

For an angle θ in QIII, θ ref = θ - π

For an angle θ in QIV, θ ref = 2π - θ

For A.

This angle is in QII ⇒ θ ref = π - θ

                                   θ ref = π - =

For B.

This angle is equal to

This angle is in QII ⇒ θ ref = π - θ

                                   θ ref = π - π = 0

For C.

This angle is equal to

This angle is in QI ⇒ θ ref = θ =

For D.

This angle is equal to

This angle is in QI ⇒ θ ref = θ =

The correct answers are A,C and D.

Notice that in the angles bigger than 2π we subtract multiples of 2π to know in which quadrants are the angles.

center= (-2,0)

radius= sqrt2/2

step-by-step explanation:

i am thinking c. sorry if im wrong .

step-by-step explanation: