Activity for re89j‭

Type	On...	Excerpt	Status	Date
Comment	Post #287178	Where did K come from? And is there a name for the property of cylinders that they are proportional to the square of their diameter. I would expect that of perfect cubes perhaps but it is hard for me to understand how cylinders behave that way. (Not saying you're wrong, at all. I admit this c... (more)	—	over 1 year ago
Comment	Post #287175	https://search.brave.com/search?q=area+of+a+circle Look at that. the helpful snippet on the right of that search result page is incorrect. 2 pi r sounds like circumference to me not area. Pr^2 is area I think... Yup, that was it. The spreadsheet finally looks plausible. (more)	—	over 1 year ago
Comment	Post #287175	I made a sheet to run this formula and it's telling me that an 8 inch spool with 4 inch core and 6" material diameter is 50% full. That can not be. it must be less than 50% right? Since the outer two inches are larger rings than the inner two..... https://docs.google.com/spreadsheets/d/14c3QMKsYy... (more)	—	over 1 year ago
Comment	Post #285755	"it is invalid to divide by a quantity that "might" be zero [because] it [can cause] you to lose solutions" ^^ +1 THIS ^^ I wonder if it's just zero, or if it's any unknown value.... Dividing by an indeterminate value [can | does always] collapse a dimension of the problem, and so presents f... (more)	—	about 2 years ago
Comment	Post #285755	Is it accurate to say it is "not allowed" to divide both sides by something that includes a variable unless I can prove some other way that the denominator I'm creating can not result in 0? In other words, I could divide both sides by a finite number or pi or something, but probably not by the var... (more)	—	about 2 years ago
Comment	Post #285755	So if 4ab=12b, and you want to know what a is, is it a bad idea to divide both sides by b? Is this example fundamentally different from dividing both sides by (5-x)? If so, why? (more)	—	about 2 years ago