Question

A variable force of
7x−2
pounds moves an object along a straight line when it is x feet from the origin. Calculate the work done in moving the object from
x = 1
ft to
x = 19
ft. (Round your answer to two decimal places.)

Answer 1

7x^-2*

Answer 2

integral of F dx
assuming that F is in exactly the direction of motion

7 integral dx/x^2 at 19 - at 1

-7 (1/x) at 19 - at 1

7/1 - 7/19 = 12/19