- #1

go_ducks

- 24

- 0

Some examples.

I needed to do this derivation for a standing wave formula

sin a + sin b = 2 sin (a+b/2) cos ((a-b)/2)

Took me 4 hours to get from sin (a+b/2) + sin(a-b)/2 = 2 sin a cos b to that formula, I finally just googled and found out its some bonehead algebra substitution. Right. Okay, I can actually get a A in electrostatics physics module, undergraduate level... but I can't recognise I need this kind of simple operation.

Also, in my lab I had a formula to derive, begin with something like F = 1/L (v/mew)^1/2

and I was supposed to derive df/F

alright, take the logs of both sides, then do partials. I didn't see that at all and still don't know how to solve the problem correctly with the method told to me. This is easy stuff, right? My physics teacher says it is and I am lame.

So basically what I'm saying is, okay, I'm past multivariable calc already, I've covered bigger things than this stuff, so I'm not going to waste my money on more bad maths teachers.. where can I get help with this sort of thing? Real help. I need some kind of starting point.