Solve Tricky Integral: \int \sqrt{\theta+\frac{1}{2}\theta^{-1/2}}d\theta

  • Thread starter Thread starter Stratosphere
  • Start date Start date
  • Tags Tags
    Integral
Click For Summary

Homework Help Overview

The problem involves evaluating the integral \(\int \sqrt{\theta+\frac{1}{2}\theta^{-1/2}}d\theta\), which appears to present challenges in determining an appropriate method for integration.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • Participants discuss potential substitution methods, with one suggesting \(u=\sqrt{\theta}\) and another proposing \(u=\sqrt{2}\theta^{3/4}\). There is uncertainty about the effectiveness of these substitutions and whether they simplify the integral adequately.

Discussion Status

The discussion is ongoing, with participants exploring different substitution techniques and expressing varying levels of confidence in their approaches. Some participants are questioning the initial steps and the reasoning behind the suggested substitutions.

Contextual Notes

There is a mention of using an online calculator, which has led to some discomfort regarding the learning process. Participants are focused on self-learning and are cautious about relying on external tools.

Stratosphere
Messages
373
Reaction score
0

Homework Statement


I can't seem to figure out what I need to do in order to solve this one.
[tex]\int \sqrt{\theta+\frac{1}{2}\theta^{-1/2}}d\theta[/tex]


Homework Equations





The Attempt at a Solution



I haven't the slightest clue as to what technique to use, it doesn't look to be a u substitution problem though (I could be wrong).
I typed it in on an online calculator and I got some really strange expression.

http://integrals.wolfram.com/index.jsp?expr=%28x%2B1%2F2x^%28-1%2F2%29%29^%281%2F2%29&random=false
 
Last edited:
Physics news on Phys.org
It is a substitution problem. Since you already cheated and looked at wolfram you may as well use that cheat. Look at the argument of the ArcSinh. That suggests if you substitute u=sqrt(2)x^(3/4) you should be able to reduce it to something you can handle. In fact, once you hack through the radicals you should be able to show that aside from the numeric factors, it becomes sqrt(u^2+1)du. Can you integrate that?
 
I don't want to use wolfram, I just used it because I couldn't figure it out. I didn't cheat on homework or anything I am self learning it. So what would be the first step starting from the original equation.
 
Well, just glancing at the integral it seems like the substitution [itex]u=\sqrt{\theta}[/itex] is a decent place to start...have you tried that? If so, how far did you get with it?
 
Stratosphere said:
I don't want to use wolfram, I just used it because I couldn't figure it out. I didn't cheat on homework or anything I am self learning it. So what would be the first step starting from the original equation.

I'm exaggerating on the 'cheating' aspect. But I already suggested an initial substitution in my last post.
 

Similar threads

  • · Replies 5 ·
Replies
5
Views
3K
  • · Replies 4 ·
Replies
4
Views
2K
  • · Replies 19 ·
Replies
19
Views
3K
Replies
3
Views
2K
Replies
2
Views
2K
  • · Replies 22 ·
Replies
22
Views
3K
  • · Replies 105 ·
4
Replies
105
Views
11K
Replies
7
Views
2K
  • · Replies 5 ·
Replies
5
Views
3K
Replies
9
Views
3K