Question

if sin (A+B)=1 and sin (A-B)=1/2;0B,then find A ndB

Answer 1

We know, Sin 90 = 1 & Sin 30 = 1/2

So, A + B =90 & A -B =30

in eq (ii), A=30 + B Now, substitute it in (i)

30+B+B=90

2B=60

B=30 & A=60

Answer 2

As Sin 90°=1 and Sin 30°= 1/2
Sin (A+B)= Sin 90, Sin (A-B) =Sin 30
⇒A+B=90 and A-B= 30
⇒2A=120
⇒ A= 60
Now putting the value of A in A+B=90
60+B=90
⇒B=30
∴ A = 60 and B=30