Solving Indefinite Integrals: ∫1/(t*ln(t)) & ∫1/(√(t)*[1-2*√(t)])

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Justabeginner
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Homework Statement


[itex]∫1/(t*ln(t)) dt[/itex]

[itex]∫1/(√(t)*[1-2*√(t)]) dt[/itex]


Homework Equations





The Attempt at a Solution



I used u-substitution for both. For the first equation, my u= ln t, and my final answer was ln|u| + C, or ln(ln(|t|) + C. For the second equation, my u= 1-2*√(t) and my final answer was -ln(u) or -ln(1-2*√(t)) + C.

But both of these are wrong, so I'm not sure what I did wrong. Can I get some guidance on this? Thank you. :)
 
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Justabeginner said:

Homework Statement


[itex]∫1/(t*ln(t)) dt[/itex]

[itex]∫1/(√(t)*[1-2*√(t)]) dt[/itex]


Homework Equations





The Attempt at a Solution



I used u-substitution for both. For the first equation, my u= ln t, and my final answer was ln|u| + C, or ln(ln(|t|) + C. For the second equation, my u= 1-2*√(t) and my final answer was -ln(u) or -ln(1-2*√(t)) + C.

But both of these are wrong, so I'm not sure what I did wrong. Can I get some guidance on this? Thank you. :)

Both of those are correct as far as integration goes. Must be an error in the answering system.
 
Oh wow, that makes me feel better now. Thank you! :)
 
Thank you! That site helps.