Angle α lies in quadrant II , and tanα=−12/5 . Angle β lies in quadrant IV , and cosβ=3/5 .
What is the exact value of sin(α+β) ?
Check this:
https://socratic.org/questions/if-sin-alpha-4-5-and-alpha-lies-in-quadrant-ii-cos-beta-5-13-and-beta-lies-in-qu
