# calculus

posted by cynthia

A variable force of
7xâˆ’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

1. cynthia

7x^-2*

2. Damon

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

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