math
posted by al .
A constant force 6i2j1k moves an object along a straight line from point (8, 6, 9) to point (5, 3, 3).
how do you find the work done

Take the scalar "dot" product of the force vector and the displacement vector. The displacement vector is
13i +9j +12k
(13)*(6) + 9*(2) + 12*(1)
= ?