The trigonometric expression cos (π/2 + r) is equivalent to the negative of sin r. Then the correct option is C.
Trigonometry deals with the relationship between the sides and angles of a right-angle triangle.
The trigonometric expression is given below.
[tex]\cos (\dfrac{\pi}{2} + r)[/tex]
We know that the formula
[tex]\cos (\dfrac{\pi}{2} + r) = -\sin r[/tex]
Thus, the cos (π/2 + r) is equivalent to the negative of sin r.
More about the trigonometry link is given below.
https://brainly.com/question/22698523
