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Why U Substitution Here

  • Thread starter bmed90
  • Start date
  • #1
99
0

Homework Statement




the integral of 1/(1-y)dy

Homework Equations





The Attempt at a Solution



ln|1-y|+C

however I believe you use u substitution as 1-y=U? Why is this so?


Homework Statement





Homework Equations





The Attempt at a Solution

 

Answers and Replies

  • #2
LeonhardEuler
Gold Member
859
1
You lost a minus sign in your solution. Making a substitution would work because the integral would reduce to
[tex]\int{-\frac{1}{u}du}[/tex]
which is well known, but this example is simple enough that you could solve it just by looking at it.
 

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