Anyone have a good 'geometry cheat sheet'?

Rhino

I still remember the simple formulas (area, etc) from grade school; but lately I've been coming across more "complex" objects that I never memorized. Anyone have a big list of geometry formulas? My google foo is off.

Ideally, something that is printable and I could use in the library while doing homework.

UrQuanLord88

Even if you do find a good cheat sheet, the best is to make one yourself. Noone knows what "complex" objects you are talking about better than you do and it would be better to make a list that can cater easily to your own needs.

Also you refine your list making skills. Therefore you win-win

DevoutlyApathetic

As far as area goes it's mostly breaking down the complex shapes into those simple ones. Could you give more examples of what you are asking about?

musanman

There are very very few formulas I couldn't sit down and derive, and it's not because I'm a super genius. Basic trig and a couple circle formulas are going to get you through anything in 2d.

Try to figure them out by breaking shapes into smaller ones, I assure you you'll learn (and remember) a helluva lot better than trying to memorize a cheat sheet.

RadicalTurnip

Yep, I always just memorized a few... The area of a triangle: ½bh (base times height). rectangle: bh. Circle: πr^2.

From those three, you can pretty much do anything with 2D shapes. For 3D, it gets a bit more messy, but you have 4/3πr^3, and the realization that the area of the base of the object of almost anything else is going to be multiplied by the height and a number of some sort: For Cones I believe it's (πhr^2)/3 and things like that.

Edit: As for cheat sheats, here's one...not amazing, but...I dunno.
http://www.abcteach.com/free/v/volume_area.pdf

Infidel

That cheat sheet has at least one error (surface area of cylinder).

Rhino

DevoutlyApathetic wrote: »

As far as area goes it's mostly breaking down the complex shapes into those simple ones. Could you give more examples of what you are asking about?

Triangular prism or 3 dimensional Trapezoids and Ellipses (whatever their official names are)

Like others have said, sure I can derivatives these with enough time [and most importantly, motivation], but but when I need a surface or area of one of these in an application problem; I'd rather just punch it in. Even if I do figure em out, it's hard to tell if I'm correct and/or have the most optimal formula.