Finding the Antiderivative of a Reciprocal: Step-by-Step Guide

cemar.
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1. Find the antiderivative of 1/(x+3)^2

Okayy i knwo this is an easy problem but i COMPLETELY forget how to do it.
Ive tried using partial fractions but it doesn't seem to be working.
I just need to know how to start the problem then i should be alright from there.
Thank you!
 
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\int\frac{dx}{(x+3)^2}

u=x+3
du=dx

You need a major review! Makes no sense ... you can evaluate Integrals using Partial Fractions but yet you've forgotten basic u-sub? Weird.
 
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oh gosh.
IIIII'm just going to go hang myself right now.
Ill just use the excuse that I am smack dab in the middle of midterms thus in the state of mind that every thing is harder than it should be.
Thanks ... i definitely won't let myself make the same mistake again.
 
Tell him what you really think, roco! :rolleyes:

cemar, he's right. By attempting to use partial fractions you're trying to use a sledgehammer when a nutcracker will do. :smile: You should hit the calc book and review the chapter entitled "Techniques of Integration" or something like that. Most calc books lay the material out in the order in which you should be thinking of them, kind of like a mental checklist. u-sub is invariably first, and that is the first thing you should try when confronted with a nonelementary antiderivative.
 
**her.
And thanks I am definitely planning on getting the hardcore review on after that slightly embarassing display of where I am at in calculus right now.
And for the record sledgehammers are a lot funner to use than nutcrackers.
=)
 
Lol, don't worry about it. You're stressed but remember, stay grounded and simple!

Wish you the best on your midterm :)
 
Prove $$\int\limits_0^{\sqrt2/4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx = \frac{\pi^2}{8}.$$ Let $$I = \int\limits_0^{\sqrt 2 / 4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx. \tag{1}$$ The representation integral of ##\arcsin## is $$\arcsin u = \int\limits_{0}^{1} \frac{\mathrm dt}{\sqrt{1-t^2}}, \qquad 0 \leqslant u \leqslant 1.$$ Plugging identity above into ##(1)## with ##u...
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