`ABC` is triangle, right angled at A. The resultant of the forces acting along `vec(AB). vec(AC)` with magnitudes `1/(AB)` and respectively is the force along `vec(AD),` where D is the foot of the perpendicular from A onto BC. The magnitude of the resultant is-

Options

A. `((AB)(AC))/(AB + AC)`
B. `(1)/(AB) + (1)/(AC)`
C. `(1)/(AD)`
D. `(AB^(2) + AC^(2))/((AB)^(2) (AC)^(2))`

Answer

C