Is the Tabular Method the Easiest Way to Solve Integrals?

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Discussion Overview

The discussion revolves around the evaluation of integrals, specifically comparing the traditional integration by parts method with the tabular method. Participants explore the effectiveness and ease of using the tabular method for solving integrals, while also addressing a specific integral involving the function $\csc^2(6x)$.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant presents an integral involving $x \csc^2(6x)$ and attempts to solve it using integration by parts, expressing uncertainty about the correctness of their solution.
  • Another participant suggests that the first participant has mixed up their variables in the integration by parts setup and provides a corrected version of the integral solution.
  • A third participant introduces the tabular method, describing its structure with $u$ and its derivatives in one column and $dv$ and its antiderivatives in another.
  • Another participant expresses appreciation for the tabular method, suggesting that the integration by parts method was used primarily for illustration rather than as a complete proof.
  • One participant mentions that the tabular method is also referred to as the "Stand and Deliver" method, citing its appearance in a movie.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the effectiveness of the tabular method versus the integration by parts method. There are mixed opinions on the clarity and utility of the methods discussed.

Contextual Notes

There are unresolved aspects regarding the correctness of the initial integral solution and the potential confusion in variable assignments. The discussion does not clarify the full implications or applications of the tabular method.

Who May Find This Useful

Readers interested in integral calculus, particularly those exploring different methods of integration, may find this discussion relevant.

karush
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$\textsf{1) Evaluate the integral}$
\begin{align*}
I_1&=\int x \csc^2 6x \, dx\\
u&=6x\therefore du=dx\\
dv&=\csc^2(6x) \, dx \therefore v=-\frac{1}{6}\cot(6x) \\
u&=6x\therefore du=6 \, dx \\
I&=-\frac{1}{6} x\cot(6x)+\frac{1}{36}\int \cot(u) \, dx\\
&=\color{red}{
-\frac{1}{6} x\cot(6x)
+\frac{1}{36}\ln(|\sin36)|)}
\end{align*}

Ok I think this is correct, if so
saw another student use the tabular method to solve this
but couldn't see good enought to understand it
is that a lot easier.:cool:
 
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I think you've gotten your $u$'s mixed up. We are given:

$$I=\int x\csc^2(6x)\,dx$$

Let:

$$u=x\implies du=dx$$

$$dv=\csc^2(6x)\,dx\implies v=-\frac{1}{6}\cot(6x)$$

Hence:

$$I=-\frac{x}{6}\cot(6x)+\frac{1}{6}\int \cot(6x)\,dx=\frac{1}{36}\ln\left|\sin(6x)\right|-\frac{x}{6}\cot(6x)+C$$

I don't know anything about the "tabular method." :D
 
tabular integration ...

$u$ and its derivatives in the second column

$dv$ and its antiderivatives in the third column

View attachment 6450
 
Last edited by a moderator:
well that is certainly much more usefull

I guess the uv method was to illustrate how it works short of a full proof

like your chart!
 
This method is also called the "Stand and Deliver" method, because it was featured in that movie.
 

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