`O` is the centre of an equilateral triangle `ABC`. `F_(1), F_(2)` and `F_(3)` are the three forces acting along the sides `AB, BC` and `AC` respectively. What should be the value of `F_(3)` so that the total torque about `O` is zero?

Options

A. `F_(1)+F_(2)`
B. `F_(1)-F_(2)`
C. `(F_(1)+F_(2))/(2)`
D. `2(F_(1)+F_(2))`

Answer

A