If f (t) = A sin ωt + B cos ωt is written as f (t) = D sin (ωt + φ ) then 'φ' is equal to?

If f (t) = A sin ωt + B cos ωt is written as f (t) = D sin (ωt + φ

1.	If f (t) = A sin ωt + B cos ωt is written as f (t) = D sin (ωt + φ ) then 'φ' is equal to?
A.	tan-1(A/B)
B.	√(A2 + B2)
C.	tan-1(B/A)
D.	A + B
Answer» D. A + B