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Differential equations - finding solution

  • #1
Select the correct solution for dy/dx = 1/[(4y)*(x^3)]

a) x^4
b) x^(-1/4)
c) 1/(x^4)
d) x root 4

Choice D means instead of cubic root, to the power 4 root

Plz explain how to do this. I tried separating variables and integrating the choices but it didn't work. Mayb I should differentiate the solutions instead?

Advice greatly appreciated
 

Answers and Replies

  • #2
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You're making this harder than it needs to be. The problem isn't asking you to find the solution -- just say which of four given functions is a solution.

For each of your four possible answers, take the derivative and see whether it is equal to 1/[(4 times the function)*x^3].
 
  • #3
LCKurtz
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None of the answers are correct, so it is no wonder that when you solved it by separation of variables, nothing worked.
 

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