Lennard Jones Potential Equation: Repulsive and Attractive terms?

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http://www.ph.qmul.ac.uk/phy108/CM2008_week2_exercise1_solution.pdf

The L-J Potential Curve in question 2),

V(r) = V(r) repulsive + V(r) attractive

Is the ^12 term the repulsive term and ^6 is the attractive term?
 
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Well, \textbf F=-\nabla V...what sign does an attractive force have? Which term in the potential produces a force with that sign?
 
Alternatively, keeping in mind that the force acts in the direction of lower potential:

Image a graph of 1/r12. Is that an attractive or repulsive potential?

Do the same for a graph of -1/r6
 
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