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

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The integral ∫t ln(t + 2) dt can be solved using integration by parts, applying the formula ∫udv = uv - ∫vdu. The correct assignments are u = ln(t + 2) and dv = t dt, leading to v = t²/2. The solution involves simplifying the integral into manageable parts, specifically ∫(t²/(t + 2)) dt, which can be further broken down into simpler integrals. The final result includes a constant of integration, C, and requires careful attention to each step to avoid errors.

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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?
 
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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?
 

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