Find the integral. (Note: Solve by the simplest method )

  • Thread starter Thread starter chapsticks
  • Start date Start date
  • Tags Tags
    Integral Method
Click For Summary

Homework Help Overview

The discussion revolves around finding the integral of the function ∫t ln(t + 2) dt. Participants are exploring different approaches to solve this integral, emphasizing the need to use the simplest method as indicated in the problem statement.

Discussion Character

  • Exploratory, Mathematical reasoning, Problem interpretation

Approaches and Questions Raised

  • Participants are attempting integration by parts, identifying u and dv, and expressing the integral in terms of these variables. There are questions regarding the correctness of the integration steps and the simplification of terms. Some participants suggest checking specific parts of the integration process for accuracy.

Discussion Status

The discussion is ongoing, with participants providing feedback on each other's attempts. There is an acknowledgment of potential errors in the integration steps, and some guidance is offered regarding the simplification of expressions. Multiple interpretations of the integral setup are being explored.

Contextual Notes

Participants are working under the constraint of solving the integral by the simplest method, which may influence their approach and reasoning. There is a focus on ensuring that all steps are clearly articulated and simplified appropriately.

chapsticks
Messages
38
Reaction score
0

Homework Statement



Find the integral. (Note: Solve by the simplest method - not all require integration by parts.)
∫t ln(t + 2) dt

Homework Equations



∫udv=uv-∫vdu

The Attempt at a Solution



dv=tdt v=tdt=t2/2
u=ln(t+2) du=1/(t+2)dt

∫t ln(t + 2) dt
=(t2/2)ln(t+2)-(1/2)∫(t2/2)dt
=(t2/2)ln(t+2)-(1/2)∫(t-2+(4/(t+2))dt
=(t2/2)ln(t+2)-(1/2)[(t2/2)-2t+4ln(t+2)]+C
=? Idk why I keep getting it wrong?
 
Physics news on Phys.org
chapsticks said:

Homework Statement



Find the integral. (Note: Solve by the simplest method - not all require integration by parts.)
∫t ln(t + 2) dt

Homework Equations



∫udv=uv-∫vdu

The Attempt at a Solution



dv=tdt v=tdt=t2/2
u=ln(t+2) du=1/(t+2)dt
Leave that red part out.
∫t ln(t + 2) dt
=(t2/2)ln(t+2)-(1/2)∫(t2/2)dt
Check the vdu in that last integral.
 
chapsticks said:

Homework Statement



Find the integral. (Note: Solve by the simplest method - not all require integration by parts.)
∫t ln(t + 2) dt

Homework Equations



∫udv=uv-∫vdu

The Attempt at a Solution



dv=tdt v=tdt=t2/2
u=ln(t+2) du=1/(t+2)dt

∫t ln(t + 2) dt
=(t2/2)ln(t+2)-(1/2)∫(t2/2)dt

The above line should be:
\displaystyle (t^2/2)\ln(t+2)-(1/2)\int \frac{t^2}{t+2}\,dt\,.​
=(t2/2)ln(t+2)-(1/2)∫(t-2+(4/(t+2))dt
=(t2/2)ln(t+2)-(1/2)[(t2/2)-2t+4ln(t+2)]+C
=? Idk why I keep getting it wrong?
 
it reads okay to me, although you missed a step. are you not simplifying enough?
 

Similar threads

  • · Replies 1 ·
Replies
1
Views
1K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 1 ·
Replies
1
Views
2K
Replies
6
Views
3K
Replies
9
Views
3K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 8 ·
Replies
8
Views
2K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 2 ·
Replies
2
Views
1K
  • · Replies 3 ·
Replies
3
Views
2K