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Can anyone tell me where I can find the entire Art of Problem Solving series (including solution manuals) or any part of the series at all? I could only find the Introduction to Algebra book after scouring the typical torrent/direct download sites on the /sci/ guide.

For those who've dealt with Vanillin + NaBH4 reaction: So I've got the vanillin/ethanol and BH4/NaOH solutions mixed together, and will add HCl until it's acidic. Then I plan on ice bathing this to get a precipitate of the vanillyl alcohol. Looking at some online procedures and a video, this is as far as they go, but one or two others take this precip and do a ethanol heating/evap process to it. So for those who have experience with this, is that really needed (or in other words, did you do that)?

Is there gravity underwater? Today I was in my swimming pool and it occurred to me that when underwater, I'm effectively weightless. I can float freely, which seemingly goes against the theory of gravity. I can spin, twist and do nearly anything in suspended or slow motion. Thus, I believe that gravity does not exist underwater. Prove me wrong. I also discovered you can get sunburned underwater. The cooling effect of the water means you don't feel the burn, though...

How would you start a proof of "there exists an infinite number of rational numbers between 0 and 1"? I know I have to do a proof by contradiction, but where do I go from there?

How do you express 127/10 as a common fraction where the denominator is a power of 2? I read this exercise in a programming book with no solutions to be found. I realize this is an ultra pleb question, but can you guys show me the method to solve this?

Just finished my last math class (multivariable calc) for my engineering undergrad. Its kind of sad that I'm officially done with math. So I was wondering what math classes should I take after mutlivariable calc for fun? Anything that will help in engineering?

I don't understand well ordering... I understand that the axiom of choice has been found to be equivalent with some statement about well ordering sets but what is that statement exactly. Basically, what sets can you well order. If I am not mistaken, you can well order the reals, but as far as I know it hasn't yet be done. My main question is, what sets are well order-able? What are the requirements?

does anyone have an interesting tutorial series, or large self-directed project that focuses on object oriented programming? a book would be nice too, but i find projects more engaging, since it forces you to properly implement something (a skill i fiercely lack). i know about project Silk and project Hilo. http://msdn.microsoft.com/en-us/library/hh396380.aspx http://msdn.microsoft.com/en-us/library/windows/desktop/ff795783.aspx i'm just trying to see if there's other things out there

Hey, /sci/, I wanted to ask, if maybe someone of you had any good materials about tensor analysis. I would be very grateful!

I usually don't do this but I need help, I have no idea on how to do a problem like this. In return here is Star Wars. That's science right Jasper Metals is considering installing a new molding machine which is expected to produce operating cash flows of $73,000 a year for 7 years. At the beginning of the project, inventory will decrease by $16,000, accounts receivables will increase by $21,000, and accounts payable will increase by $15,000. All net working capital will be recovered at the end of the project. The initial cost of the molding machine is $249,000. The equipment will be depreciated straight-line to a zero book value over the life of the project. The equipment will be salvaged at the end of the project creating a $48,000 aftertax cash flow. At the end of the project, net working capital will return to its normal level. What is the net present value of this project given a required return of 14.5 percent?

sup /sci/ I need some kind of function, the simpler the better, that looks like pic related. Periodic, but with the times where it is positive and negative unequal. I was thinking I could just have a sine function plus some constant, but I'm not sure how to mathematically relate the constant to the ratio of positive/negative. Any ideas?

If someone was born 9,452 days ago, what is their birthdate? In return, a hairless bear.

SpaceEngine thread should be here or on >>>/v/ ? On screen is a planet without night, in binary system

So there is the real axis and the imaginary axis. Is there a 3rd? Does it go on forever?

If your car fell off a cliff, would it be physically possible for you to open the trunk and leap into a tree before the car crashes into the ground? Assuming the tree was huge (like redwood sized) and it actually had branches.

does anyone have a link to some theory on torsion, for example torsion on a wire due to an applied torque?

Hi /sci I dont know if you can help me with this, but I feel like I'd ask. I recently got prescribed a new antidepressant by the health center at my college. It works great, but sometimes when I try to go to sleep, it feels like there's a light that' shining behind eyes. It really hurts and I cant sleep when it happens. does anyone know why this is happening, or at least what it's called so I can do more research on it? pic unrelated, but everyone loves fluffy things

does anyone know CAD/CAM? I need to learn it because it will be helpful for me at the end of my degree. can i learn it for free? I have a while to do it I just want to start tinkering and get comfortable with using it. are there programs similar to it? any help if appreciated >tldr how to learn CAD/CAM for free?

Just wondering if there is a name for this. It's kinda like the rule of Sarrus for finding the determinant of a 3x3 matrix, but it gives you the matrix of minors. The arrangement is just a simple way to get the minors. I have looked, but I couldn't find any name this particular arrangement.

Outer Space Thread