How Is Work Calculated When a Force Varies with Position?

[b-pipe]

Homework Statement

A force acting on an object moving along the x-axis is given by F_x = 10x-2.0x² N where x is in m. How much work is done by this force as the object moves from x = -1 to x= +6

Distance = 7 m

Homework Equations

Work = Force * Distance cosine theta

The Attempt at a Solution

The equation for force is already given so I found force by integrating the equation F_x = 10x-2.0x² to get F_x = 10-4.0x then I substituted the x for 7 to get -18 Joules. The problem I have is that the answer I got isn't among the options.

 

[Yuqing]

You differentiated instead of integrated.

 

[mukundpa]

and Put the limits for x properly from -1 to +6, (Wx=+6 - Wx=-1)

 

[b-pipe]

You differentiated instead of integrated.

and Put the limits for x properly from -1 to +6, (Wx=+6 - Wx=-1)

Oh, I see thanks.