Answer:
-⅘
Explanation:
Take cos⁻¹ -⅘ to get your x-value of -2,498091545 [radians], then plug it into the sine function to get this:
-sin(-2,498091545 + π\2) ≈ -⅘
↑
This negative is on the outside according to the Trigonometric Identity rules, and that it lies in Quadrant III.
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