# Are proofs from calc class needed for EE?

1. May 14, 2017

### sk2017

Hi,

I am a first year calculus two student. I found that I have serious trouble understanding the derivation of formulas. For example, I can solve most of the exam problems because they are just using formulas, say arc length = Integral(sqrt( 1+ (dy/dx)^2)dx, but my textbook actually has two pages dedicated to how this formula is derived. I've looked at youtube videos and "kind of" understands it, but certainly not to the degree my textbook explains. I found it extremely troubling when doing center of mass problems, because the textbook dedicated 4 pages of work to reach the final formula, and I can't even find one place online that says anything else than "here's the formula and just use it."

so basically, I can just do algebra provided with a formula (i'm not even good at algebra...), except with integral signs and derivatives. Is one suppose to understand this math stuff for an EE job or is using formulas all that's required?

2. May 14, 2017

### Staff: Mentor

Wow, don't give up. I remember when I was a senior in engineering school. I recall thinking that learning how to derive my own equations to fit the problem was by far the most valuable skill I learned in all my years of school. Facts you can look up in books. Even specific concepts and understanding of physics may or may not be useful on your job. But two things are certainly useful for engineers, 1) doing your own derivations, and 2) a feel for numbers so that you can guess the approximate answer without calculating. Slide rules in my day, helped a lot with #2.

But learning how to derive equations is not the subject of any course I had. Just seeing it done in class and then doing homework problems is what makes the light bulb light eventually.

Do you participate in study groups? Sometimes students learn best from each other.

I repeat, don't give up.

3. May 16, 2017

### jasonRF

As an EE, I agree with anorlunda. The ability to derive things is a useful skill for EE.

However, in my case it took years to really develop the skill. I started to work at it my sophomore year, after watching my physics TA skillfully answer any question we asked by starting from first principles and deriving the answer.

For me, whenever a subject captured my imagination (electromagnetism and probability my sophomore year) i would spend some time learning some of the derivations and practicing related derivations that often showed up as example problems in textbooks. Time limitations of course meant that I had to pick and choose when to invest time this way (you will not have time to do everything!)

I also found that I really learned to understand calculus derivations in subsequent physics and engineering classes. So you will have many more opportunities to learn this stuff. Likewise, next year you will probably learn vector calculus, and your upper division eletromagnics course will help you understand it better.

So do not fret. You are on the same track many of us were at your stage.

Jason

4. May 25, 2017

### sk2017

Thanks for sharing! I feel much better