Question

Which of the following sum of angles is useful in evaluating the trigonometric expression?

Answer 1

Case: Trigonometry (double angles)

Given:

`sin((17\pi)/(12))`

Required: To select a sum of angles is useful in evaluating the trigonometric expression

Method:

Check the options that can be simplified to any image in the picture:

First we evaluate the angle in such a way that it forms a special angle

`sin((17\pi)/(12))`

Testing

Option A can be reduced to

`(5\pi)/(4)+(\pi)/(6)`

Option E can be reduced to:

`(2\pi)/(3)+(3\pi)/(4)`

Option F can be reduced to:

`(\pi)/(4)+(7\pi)/(6)`

Final answer:

Options A, E and F are correct