If sin A= 1/4 and sin B= -1/2, with A in QII and B in QIV, find tan(A+B)

Answer 1

in QII if sinA = 1/4, tanA = -1/√15
in QIV, if sinB = -1/2, tanB = -1/√3

tan(A+B) = (tanA+tanB)/(1-tanAtanB)
= (-1/√15 - 1/√3)/(1-1/√15√3)
= (√3+√15)/(√45-1)

Answer 2

Oops. That would be

-(√3+√15)/(√45-1)