Question

plz help me......... 12 question

Answer 1

∵sinα=1/2
∵sin30=1/2
∴α=30
∵cosβ=1/2
∵cos60=1/2
∴β=60
∴α+β=90

Answer 2

let alfa=A nd beeta=B
sin (A+B)=sinAcosB+CosAsinB
is sinA=1/2 then cosA=root3/2
cosB=1/2 then sinB=root3/2
now
sin (A+B)=1/2×1/2+root3/2×root3/2
=1/4+3/4
=1
so the value of A+B=90°
means....alfa+beeta=90°