`theta = (2pi)/3` Find the reference angle `theta ' ` and sketch `theta` and `theta ' ` in standard position.

kspcr111 | Student

These can be easily understood by converting into the degrees

so,

`theta = 2pi/3` = `2/3 ` of `180^@` `= 120 ^@`

`theta '` = the reference angle 

The reference angle is defined as 

"The smallest angle that the terminal side of a given angle makes with the x-axis"

so the reference angle is `theta '` = `60^@` which is shown in the attachment below