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Ok ty (can u checked this one)

  • Thread starter ArmiAldi
  • Start date
  • #1
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let me know is this correct or no?
dx)/(x lnx^4)
(dx)/(x 4lnx)
(dx)/(4x lnx)
u = lnx
du/dx = 1/x
(du)(x) = dx

lnx = u dx = (du)(x)

(du)(x)/(4x u)
du/4u
(1/4)ln(u)


(1/4)ln(lnx)
 

Answers and Replies

  • #2
cristo
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I am moving this question to the homework forums. Please post all homework/coursework questions there in future!
 
  • #3
HallsofIvy
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let me know is this correct or no?
dx)/(x lnx^4)
You mean the integral of this don't you?

(dx)/(x 4lnx)
(dx)/(4x lnx)
u = lnx
du/dx = 1/x
(du)(x) = dx

lnx = u dx = (du)(x)

(du)(x)/(4x u)
du/4u
(1/4)ln(u)


(1/4)ln(lnx)
Well, (1/4) ln(ln(x))+ C. And you didn't really need to write "(du)(x)/(4x u)". From du/dx= 1/x, du= dx/x and you can go ahead and substitute du for the dx/x you already have in the integral.
 

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