Calculating Work with Kinetic Energy in Orbit

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Homework Statement


A 62kg satellite orbits the Earth with a radius of 3.3*10^7 m. A net external force acts on the satellite to an orbit of 7.7*10^6 m, what work must the external force do?


Homework Equations


W = integral of F with respect to d


The Attempt at a Solution



Integrate F which in this case is GMm/r^2 which becomes -GMm/r, then plug in the radii. However, the answer that I got was -2.46*10^9, which is incorrect.
 
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You need to include the kinetic energy as well, because the velocity of the satellite
in a lower orbit will be bigger
 
willem2 said:
You need to include the kinetic energy as well, because the velocity of the satellite
in a lower orbit will be bigger

How would I include the kinetic energy?

Would I approach it as this?

GPE = gravitational potential energy
KE = kinetic energy


GPEfinal + KEfinal = GPEinitial + KEinitial + Workof external force ?