Question

Question #7b448

Answer 1

The relationship of any angle to a ( first quadrant ) acute angle is

only contextual.

Explication:

in respect of `cos theta = cos (pi/3)`, the principal value is the acute

angle `pi/3` and the general value of theta is given by

`theta = 2npi+-pi/3, n =0, 1, 2, 3, ...`

Here, for `n = 1, theta = 7/3pi and 5/3pi`.

So, in this context, `5/3pi` and the principal acute-angle

value `pi/3` are related, as solutions of `cos theta = cos (pi/3)` .