Recent content by Vector1962

i can write the equation of circle easy enough, x^2+(y-r)^2=r^2. i get A=r^2/2 * asin((y-r)/r) + (y-r)/2 * sqrt(r^2 - (y-r)^2) through integration (using change of variable). Letting u = (y-r) and u^2=(y-r)^2, du= dy. Here's the rub... it's not right... :-) Appreciate and thanks in...

the calculation 6C4 shows 15 but what if all sets are to be distinct? meaning 1,2,3,4 is the same as 4,3,2,1. I made a tree diagram and i get 10... assuming i did that correctly...?

Excellent... thank you. for what it's worth and for the number of items involved i made the tree diagram and arrive at exactly what you suggest.

Hello Forum: I have numbers 1 through 6 from which i must select 4 items. The twist is that i need to count only those subsets that include the number 2 all of the subsets are 'distinct' --> 2145 is the same as 2415. My quick calculation yields 15 distinct subsets however some of those do...

I appreciate your reply. I don't really consider myself a scientist but rather more curious concerning the values between 50C and 100C. Seems like with the amount of information currently available regarding water that the tables and graphs would routinely go to 100C . Don't suppose you have...

Wondering why moisture ratio tables related to temperature and air only go up to roughly 50 C or so? is that temperature a "boundary" on the amount of water air can hold?

For what it's worth... Just read a paper from the University of Berkeley and they're using the wiki definition.

The following from wiki, along with other sites, "The unit foot-candle is defined as the amount of illumination the inside surface of a one-foot-radius sphere would be receiving if there were a uniform point source of one candela in the exact center of the sphere". The reason I thought it was...

I've searched around the internet and thought it would be a simple thing find and perhaps it is, but the more I dig the worse it becomes. According to online dictionary, 1 foot-candle is the amount of light from a 1 lumen light source on 1 sft of surface area at a distance of 1 foot. Sounded...

I'm sure much ridicule will follow, but my experience is that a "bad instruction" is not an excuse for failure. A student with initiative who really wants to learn any material and realizes "Good God, this instructor sucks...or this textbook is useless..." will do what it takes to get the...

You are certainly correct, hence my questions. Thank you for your reply.

Wondering if you wouldn't entertain one more question on this concerning your experiment? In part 1, in the energy state of the water molecules at 20 C they are moving at some speed V20 and if you increase their temperature their kinetic energy goes up and their velocity changes to V30. In...

I'm afraid it would have not have occurred to me to approach the problem this way. For some reason, needed to think in terms of sets and I needed a set of 6. My efforts were directed on finding how to generate sets of 6. To start by picking 3 black 'first' would not have crossed my mind...

The permutation 'gibberish' is me reading a statistics book, grasping at some straws trying to make some sense of all this. In the text it mentions "repeated" items and thought I was getting close. I realize the approach should be "Read, Understand, Do". Sometimes I just have to put something...

As long as I'm guessing, The number of ways to arrange 3 black balls from a set of 3 black balls is 3C3 = 1. The number of ways to select 3 white balls from a set of 9 white balls 9C3 = 84. The fundamental counting principle indicates the number of ways to pair these 2 sets together is to...