/sci/ - Science & Math

>integrals
>hard
>this generation
world is kil

>>6802539
I'm sorry if I'm not a genius. And if this generation is kill it's fault of people like you.

>>6802539
>>6802552
this world*

It's okay Pedro, don't worry. You don't need to know integrals to mow my lawn.

>>6802581
>>6802539
lol, now i got it

>>6802531
Ignore this dude he's clearly got a superiority complex. Khan Academy is pretty good for most maths up to and including some degree level I believe.

http://www.wolframalpha.com/

There pedro, that website is your new religion now.

>>6802531
you can probably get mathematica from your uni for cheap. Consider that.

If you want reassurance, once you get past DiffEq, most of CivE just kind of glosses over Integrals. You only really use them in beam theory. Solid Mechanics is more worried about general tensors and you rarely do a 'calculus-type' homework problem. Even in fluid mechanics in CivE at the undergrad level, most integrals are very simple and are used mostly for things like momentum conservation.

The moral of the story is, learn to do it numerically and you'll do fine as as CivE. We use the concepts all the time, but rarely go through the derivation because it isn't actually important. One of my grad classes had a fairly extensive little math derivation, and none of us had used much calculus for so long that it was embarrassing how long it took us to do the problem.

>>6802531
Symbolab is another good one

<span class="math">\displaystyle \int_a^b f'(x)dx = f(b)-f(a)[/spoiler]
<span class="math">\displaystyle \int f'(x)dx = f(x)+c[/spoiler]
<span class="math">\displaystyle \int f'(g(x))g'(x)dx = f(g(x))+c[/spoiler]
<span class="math">\displaystyle \int f(x)g'(x)dx = f(x)g(x) - \int f'(x)g(x)dx[/spoiler]
<span class="math">\displaystyle \int \frac{f(x)}{g(x)}dx,\; \delta f(x) \geq \delta g(x) \Rightarrow \int q(x) + \frac{r(x)}{g(x)}dx = \int q(x)dx + \int \left( \sum_{i=1}^m \sum_{j=1}^{k_i} \frac{A_{ij}}{(x-r_i)^j} + \sum_{i=1}^n \sum_{j=1}^{s_i} \frac{B_{ij}x + C_{ij}}{(x^2 + a_i x + b_i)^j}\right)dx[/spoiler]

<span class="math">\sqrt{a^2 + x^2} \geq 0 \rightarrow \left(\sqrt{a^2+x^2}\right)^2 = a^2 + x^2[/spoiler]
<span class="math">\sqrt{a^2 - x^2} \geq 0 \rightarrow a^2 = \left(\sqrt{a^2 - x^2}\right)^2 + x^2[/spoiler]
<span class="math">\sqrt{x^2 - a^2} \geq 0 \rightarrow x^2 = \left(\sqrt{x^2 - a^2}\right)^2 + a^2[/spoiler]

<span class="math">\displaystyle t = \tan\left(\frac{x}{2}\right) \Rightarrow dx = \frac{2dt}{1+t^2}, \; \sin(x) = \frac{2t}{1+t^2},\; \cos(x) = \frac{1-t^2}{1+t^2}[/spoiler]

Oh wow, now you can solve every integral on a calculus course.

I always tell people that if they want to pass Math they have to practice it. Even I have to practice it. I need to do at least 5-10 questions a day to make sure it's at my finger tips the same way classical pianists have to practice over and over and over again. Math isn't hard, it really isn't, it's just the mental blockage people have, they see these weird symbols and letters and they begin to freak out. Practice, practice, practice. Read the theory yes, understand it, look at example questions, then just practice. It's like sports, even athletes need to train and work out, your brain is a muscle, give it a work out.

A good example in my class is that my professor gave us an assignment sheet and the following week gave us a quiz that had the very same questions, there are people who still failed. Fast forward to this week, professor is giving us a quiz, questions were in the homework, same people still complained asking for an extension, and they did bad cause I heard them grumbling outside, they haven't figured out yet that if they just did their homework they'd be getting A's. I wonder if they'll ever figure it out.

You are lucky to live in the 21st century where you have the internet at your disposal. You can google a topic, any topic and most likely some person out there has posted a tutorial or a lecture. You really don't have an excuse. It should take you a day or two to understand integrals and how they work and what they do to help, then practice problems.

All the best Pedro!

>>6802602
>>6802704
>>6802739
>>6802744
Thanks guys, I'll try it out.

>>6802864
Well, what?

>>6802886
It also happens in my uni, my teacher gives us some problems to practice and most people doesn't do it. Last week we had a quiz and most of the questions were the same as the problems he gave us to practice 3 weeks ago.

And the internet really helps if you know how to use it, sometimes I give up to some distractions but i'm working on it. I like to watch some videos and look for some exercises. It's my study source actually.

I've heard about the Pomodoro Scheme (or something like that) to study. It consist in study for 25 min and take a 5 min break to eat or relax. It is helping me a lot since the time flies and I don't feel tired.

>>6802927
It's pretty much everything you will ever need for solving single variable integrals?

Just that and knowing your trigonometric identities.

>>6802946
Ahem, you forgot that it's just for the indefinite ones. Then again, like >>6802886 has pointed out, it's all a matter of practice. Within a month or two, the actual integration becomes the easiest step.

>inb4 revolution solids, surfaces, improper integrals, multivariable, omg muh brain

>>6803213
Definite integrals are just that between two points, there really isn't anything there.

Kill yourself, dirty spic.

>>6802942
>It consist in study for 25 min and take a 5 min break to eat or relax

this.

i never sit down for a study sesh, i just always have my little notebook with me. 5 minutes in line somewhere? notebook time. go take a piss? notebook time.

i don't know if micro studying is a thing, but it should be.

>>6802531
Pencil, paper, and a brain, faglord.