Potential Energy associated with a Variable Force

[robotman]

Homework Statement

A particle moves along the x axis under the influence of a variable force F(x) = 7.9x2 + 3.4x where the force is measured in Newtons and the distance in meters. What is the potential energy associated with this force at x = 3.0 m? Assume that U(x) = 0 J at x = 0 m.

Relevant Equations

mgh

Don't really know what they want from me

 

[etotheipi]

You must start from the definition of the potential energy of a conservative force, i.e. that $F(x) = - \frac{dU(x)}{dx}$. That means, $U(x) = - \int_{\text{ref}}^{x} F(x') dx'$.

 

[BvU]

Hello @robotman , !

Don't really know what they want from me

Unfortunately, that does not count as an attempt at solution according to https://www.physicsforums.com/threads/homework-help-guidelines-for-students-and-helpers.686781/
so formally we are not allowed to help.

Informally it doesn't make it easy to help either, because we have no idea what your actual problem is.
Why on Earth do you think $mgh$ is a relevant equation ? (Do I see an equation?)