The potential energy of a configuration is expressed as U(x,y)=5x2y. The force acting the particle at (1m,1m,1m) is
-5(i^+j^)
-10i^−5j^
−5i^-10j^
10i^+5j^
F→=−∂U∂xi^−∂U∂yj^−∂U∂zk^F→=−10xy^−5x2j^−0k^At (1,1,1) F→=−10i^−5j^