Two forces each equal to `F//2` act at right angle. Their effect may be neutralized by a third force acting along their bisector in the opposite direction. What is the magnitude of that third forces.

Explanation

Rsultant of two forces:`sqrt((F//2^(2))+(F//2^(2)))=F//sqrt(2)`
The third force, should be opposite to the resultant and of same magnitude. Hence, answer is `F//sqrt(2)`.