An object of mass 2 kg is repelled from the origin by a force in the +x-direction whose magnitude varies with x according to F=(7Nxm^2)x^-2. How much work is done by this force when the object moves from x=2 to x=3? (Be sure to say whether this work is positive or negative.) I have no idea how to start this problem off. Anybody want to help me out?