Find the stationary points of: $V=(2/r^3)-(3/r^2)$











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I've applied the exponent rules and differentiated to get to the point where i have



$$dr/dv=-6r^{-4}+6r^{-3}$$



I'm starting to get very confused with the math when i set the LHS = 0 in order to find the value of stationary points.



Any guidance would be helpful.






stationary-point







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up vote
1
down vote

favorite












I've applied the exponent rules and differentiated to get to the point where i have



$$dr/dv=-6r^{-4}+6r^{-3}$$



I'm starting to get very confused with the math when i set the LHS = 0 in order to find the value of stationary points.



Any guidance would be helpful.






stationary-point







share|cite|improve this question
























  • Hi, welcome to math.SE! Please use Mathjax to format your equations.
    – Jam
    Nov 18 at 20:17















up vote
1
down vote

favorite









up vote
1
down vote

favorite











I've applied the exponent rules and differentiated to get to the point where i have



$$dr/dv=-6r^{-4}+6r^{-3}$$



I'm starting to get very confused with the math when i set the LHS = 0 in order to find the value of stationary points.



Any guidance would be helpful.






stationary-point







share|cite|improve this question















I've applied the exponent rules and differentiated to get to the point where i have



$$dr/dv=-6r^{-4}+6r^{-3}$$



I'm starting to get very confused with the math when i set the LHS = 0 in order to find the value of stationary points.



Any guidance would be helpful.






stationary-point




stationary-point






share|cite|improve this question















share|cite|improve this question













share|cite|improve this question




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edited Nov 18 at 20:17









greedoid

35k114489




35k114489










asked Nov 18 at 20:12









RocketKangaroo

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163












  • Hi, welcome to math.SE! Please use Mathjax to format your equations.
    – Jam
    Nov 18 at 20:17




















  • Hi, welcome to math.SE! Please use Mathjax to format your equations.
    – Jam
    Nov 18 at 20:17


















Hi, welcome to math.SE! Please use Mathjax to format your equations.
– Jam
Nov 18 at 20:17






Hi, welcome to math.SE! Please use Mathjax to format your equations.
– Jam
Nov 18 at 20:17












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So we have $$-6r^{-4}+6r^{-3}=0implies 6r^{-4}=6r^{-3}implies {6over r^4}={6over r^3};;/cdot r^4$$



$$implies 6=6rimplies r=1$$






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    So we have $$-6r^{-4}+6r^{-3}=0implies 6r^{-4}=6r^{-3}implies {6over r^4}={6over r^3};;/cdot r^4$$



    $$implies 6=6rimplies r=1$$






    share|cite|improve this answer

























      up vote
      1
      down vote













      So we have $$-6r^{-4}+6r^{-3}=0implies 6r^{-4}=6r^{-3}implies {6over r^4}={6over r^3};;/cdot r^4$$



      $$implies 6=6rimplies r=1$$






      share|cite|improve this answer























        up vote
        1
        down vote










        up vote
        1
        down vote









        So we have $$-6r^{-4}+6r^{-3}=0implies 6r^{-4}=6r^{-3}implies {6over r^4}={6over r^3};;/cdot r^4$$



        $$implies 6=6rimplies r=1$$






        share|cite|improve this answer












        So we have $$-6r^{-4}+6r^{-3}=0implies 6r^{-4}=6r^{-3}implies {6over r^4}={6over r^3};;/cdot r^4$$



        $$implies 6=6rimplies r=1$$







        share|cite|improve this answer












        share|cite|improve this answer



        share|cite|improve this answer










        answered Nov 18 at 20:15









        greedoid

        35k114489




        35k114489






























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