# I've always been terrible at math and want to teach myself

1. Mar 14, 2012

### redpiano

Hi

Like the title says I've been awful at math since grade school, I still don't know my multiplication tables by heart, I certainly don't know simple division even adding and subtracting takes me a second.

So needless to say I've struggled with math my entire life, I failed through gradeschool, I failed pre-algebra in junior high, twice and then again in high school before I dropped out at which point I took some GED preparedness classes and ended up just giving up on that specifically because I just don't get math, even the rather simple seeming GED math.

But I want to learn, I want to be able to look at an equation and know how to solve it and not just tilt my head and get a migraine lol. I've also been thinking about college recently and everything I'm interested in will require at least some math. So I was watching this video of Richard Feynman talking about his past and he mentioned a series of books calling "(insert type of math) for the practical man" So I immediately hunted down a .pdf of one of these books, the algebra version and in the first chapter I'm already lost, I can understand some very basic problems but once you start mixing in a bunch of letters and fractions and decimals it just becomes a total wash for me.

So if anyone has any pointers or tips for me, any books you'd recommend, anything you can tell me about how to approach math, where to start etc. I would like to this from home and not hire a tutor or take classes at the moment. But is it just a matter of ramming my head into the wall of numbers until it clicks or what?

Thanks for looking.

2. Mar 14, 2012

### PhantomPower

Time and practise and you will be able to do it. The main thing is do not give up, you have posted here so thats a great start. I recommend : http://www.khanacademy.org/ for some great beginner to advance tutorials - Do them like mini lectures take NOTES, test yourself. There is hundreds of example problems on the web.

And lastly good luck, think of the goal not just the path.

3. Mar 14, 2012

### chiro

Hey redpiano and welcome to the forums.

Once you have done enough practice to do algebra and computations, then when you get to higher math you will have to get a conceptual understanding in addition to being able to doing computations and algebra.

For this I recommend asking your teachers, lecturers, or professors or if you are doing it yourself you can ask on these forums.

The thing with math is that you need to know both the concepts and the computational aspect. If you don't understand the concept then you will get stuck every time you get an equation that you've never encountered before and if you get a question where you don't get equations but instead things like 'word problems' where you have to convert that to the mathematical representation before you do your algebra, then you will get stuck.

But before you get to higher mathematics, I would also recommend a resource like Khan Academy to work on your algebra and computation skills before you start to tackle the higher mathematical problems.

4. Mar 14, 2012

### Angry Citizen

It is distasteful, but start by learning your multiplication tables up to 10 (for reasons on which I'll elaborate later, I don't find 11 and 12 necessary to memorize). You find that everything can be broken down into multiplication and addition/subtraction - including division. The math I do as an engineering student relies heavily on being able to perform simple multiplication and addition/subtraction.

Once you're done with that, I would suggest investigating the properties of numbers. When you first run into them, the commutative/associative/distributive/etc properties don't make much sense. But using them, you can perform the aforementioned tricks involving separation of the complex into the simple. For instance, try multiplying 392x68. But why would anyone want to apply a grade-school algorithm when they can recognize that this is really (300 + 90 + 2)x(60 + 8)? In a sense, all you need to do is know what 6x3, 6x9, 6x2, 8x3, 8x9, and 8x2 is. In fact, that's where the grade-school algorithm comes from. Once you get comfortable with these processes, basic math is an exercise in bookkeeping.

A great resource is Khan Academy. Google it and run through the videos. Come to PF with questions. We'll be happy to answer anything you like, no matter how simple you may think it is. All of us were once at the stage where this kind of math troubled us, and this place is infested with physicists and engineers and mathematicians performing tensor analyses, proving esoteric theorems, and designing nuclear reactors. Like any other language, it takes years to become fluent in math, and then you'll still never be a perfect speaker.

5. Mar 14, 2012

### BeBattey

Few things:

1. No one's inherently bad at math. Our brain is a computing machine, people are only more comfortable because they had teachers more in line with how they learn, among other factors. Thinking you're bad at math while trying to learn math will get you nowhere.

2. There are some great videos on the internet that some math professors/tutors/math amateurs make up and create an unofficial math course. Check out the learning materials forum on physicsforums too. Beyond that, a simple youtube search could yield the perfect answer for you. 'Basic Algebra' or 'Factoring polynomials' or 'solving x y equations' etc. This gets me past so many of my 'blocks'

6. Mar 15, 2012

### redpiano

Thank you for the replies, I've been browsing about on khan academy and it's pretty great, I love the practice section and the helpful videos that'll all come in handy.

7. Mar 15, 2012

### Fredrik

Staff Emeritus
I haven't read it myself, but I've seen recommendations for the book "Basic mathematics" by Serge Lang. You should check it out and decide for yourself if it's right for you. (It's possible that you need something even more basic). I suggest you use the "search inside this book" feature at amazon.com. Link.

8. Mar 15, 2012

### redpiano

Right now I'm practicing multiplications because I still have trouble with any number above 5, so I'll need to work a lot on that. And I was doing one of the khan academy practice things on associative/distributive/commutative equations which I understand pretty well.

I must have just totally failed at paying attention in math class.

I really wish this site were around when I was a kid, it makes things very simple and understandable.

9. Mar 15, 2012

### Ken Lim

reapiano, do not despair, i only got a hang of math in my undergrad years. Try to understand the math instead of just blind practice, math is logic all the way, practice enforces that logic, and of course, when you have a good foundation, the logic piles up and you will feel comfortable with it.

10. Mar 15, 2012

### micromass

I'm the one who always recommends this book :tongue: But if you have troubles with multiplication, then this book is too advanced for now. Once you know basic arithmetic and algebra, you can read it.

11. Mar 16, 2012

### bael

wow. i just noticed that when you multiply two big numbers together, the product will have the same number of digits as both of the first two numbers combined. how could i have been so blind.

12. Mar 16, 2012

### QuarkCharmer

I don't think that's correct.
56*21 is 1176, so, 2 digits by 2 digits is 4 digits..

but:
50*11 is 550, so 2 digits by 2 digits is 3 digits..

13. Mar 16, 2012

### bael

whenever i start to think that math is cool something like this happens

14. Mar 16, 2012

### Angry Citizen

Don't worry, there are all kinds of really interesting relationships between numbers. Figuring out how to prove which ones are true is the real beauty of mathematics.

15. Mar 16, 2012

### QuarkCharmer

Sorry man, here is an interesting relationship to replace the one I stole from you. It always works, and it has some interesting consequences.

Any prime number (3,5,7,11,...), when squared will always equal a quantity that is exactly 1 greater than the product of the number before it and after it.

For instance, $7^{2} = 6*8+1$

Like mentioned above, part of the fun is proving whether an assumption you make is true or not. It's great that you are even thinking about things like that. You made an observation, that, in your experience, the number of digits of two quantities multiplied together is usually around the number of their products. That's a good starting point, most people don't even think about things like that. From there though, you need proof that your idea is true for all numbers before you apply it to something that may not be in the ideas domain.