Imagine you can apply three different forces F1=40 N, F2=50 N and F3=60 N to a body. The forces' magnitudes are fixed, but you can apply them in any directions in the x-y plane.
A. Make a sketch to show how you'd apply these forces to achieve the largest possible resultant force.
B. Make a sketch to show one way to apply these forces to get a 70-N resultant force, pointing in the +X direction.
C. Make a sketch proving that three forces with these magnitudes can add to give zero net force.
Answers (1)
A. All applied in the same direction
Do you really expect someone to sketch, here?
B. F3 in + x direction, F2 in + x direction, F1 in - x direction
C.
... you are on your own.