Simply cannot remember int/diff formulas

[mmapcpro]

I'm currently reviewing calculus that I learned 10 years ago, because I will be resuming an electrical engineering program in the fall.

I am simply having a heck of a time remembering all of the formulas. Basically, I'm having to look at the problem, look at the list of elementary integration/differentiation formulas, see if I can manipulate the equation to best fit one of the formulas, and then work the problem based on the best method.

For example, looking at an integration problem, and noticing, "oh hey...that's a sqrt(a^2-u^2) in the denominator...lemme see which substitution would be best to use, etc. Then once I get it in the form I want, I usually ahve to look up WHAT the integration is...for instance, arcsin(u/a) + c, in this example.

I'm nervous that I'm not going to have what it takes to be successful in this program, if I cant' even remember these formulas.

 

[phinds]

is there a question in here somewhere ?

 

[mmapcpro]

If I can't memorize all of the integration and differentiation formulas for trigs, hyperbolics, all the inverses, etc...is that going to be a big problem in my academic career? Or as long as I know what I'm looking for, is that sufficient?

 

[Hurkyl]

noticing, "oh hey...that's a sqrt(a^2-u^2) in the denominator.

see if I can manipulate the equation to best fit one of the formulas

These two are very important skills. The first one reflects the ability to look at a problem and recognize it as something you can do (or, at least, similarity to things you can do). The second reflects the ability to actually transform a problem from its given form into the form you know how to solve.

Actually memorizing the solution method for the particular form (as opposed to knowing where to look it up) is something that can be trained through practice, if it is really necessary.

 

[Nebuchadnezza]

Actually it is quite hard plainly remembering the formulas. If you derive them,or know why they work it is much easier.

If you know a few identities, everything gets easier.

$$1 + \tan(x)^2 = \sec(x)$$

This identity shows why we use the tan substitution when dealing with

$$\sqrt{a^2+x^2}$$ (Try it for yourself)

The same is with another identity

$$cos(x)^2 \, + \, sin(x)^2 \, = \, 1$$

$$\sqrt{a^2 - x^2}$$

Anyho, just do a billion problems. After a while it sinks into your blood. Here is a list of a bunch of fun integration problems. You really have to think to solve a few of these, and that should be right up your alley =)

http://www.2shared.com/document/fTXjMCFj/Integrals_from_R_to_Z.html

Also here, tad more info

https://www.physicsforums.com/showthread.php?t=498665