1. The problem statement, all variables and given/known data why for 0 <x <3 , why the author ignore the 10kN ? as we can see , the 10kN is located 3m from A ...... 2nd question is , the author assume downwards force is positive , am i right ? 2. Relevant equations 3. The attempt at a solution for 0 <x <3 , the shearing force V = 4kN , as we can can see , at A the support force (4kN) is pointing upwards , so the shearing force 4kN should be pointing downwards , am i right ? so , the author assume downwards force is positive?? if so , why in the shearing force diagram (SFD) , the 4kN is at positive x direction , shouldn't it at 4kN bottom of the x-axis ?