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Couple of prime questions... - Printable Version

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Couple of prime questions... - sol740 - 08-25-2014 09:51 AM

Before I go and buy a Prime, I have some questions. I'm using the emulator at the moment but am stuck.

These are me being lazy and testing the device (I can do these on paper fine):

1. If I have an expression a^2+2ab+b^2, with the CAS, how can I manipulate it to (a+b)(a+b)?

2. If I have an expression (a^3+3(a^2)b+3a(b^2)+b^3)/(a+b) how can I force it to evaluate the divisor symbolically and return either of the above?

3. It looks like a reasonable platform for data logging as well. Is there any StreamSmart documentation in context to the Prime? Ideally I'd like it to log temperature (300-400K) every 5 seconds for 2 hours, then be able to do some minor processing on it on the device (fourier analysis, stats)

Any help appreciated Smile

I discounted the TI CX already as the thing is horrid to use.


RE: Couple of prime questions... - Joe Horn - 08-26-2014 03:34 AM

(08-25-2014 09:51 AM)sol740 Wrote:  1. If I have an expression a^2+2ab+b^2, with the CAS, how can I manipulate it to (a+b)(a+b)?

Method 1: factor(a^2+2*a*b+b^2) --> (a+b)^2

Method 2: factors(a^2+2*a*b+b^2) --> [ a+b 2 ]

(08-25-2014 09:51 AM)sol740 Wrote:  2. If I have an expression (a^3+3(a^2)b+3a(b^2)+b^3)/(a+b) how can I force it to evaluate the divisor symbolically and return either of the above?

Just type it and press Enter. If you have CAS Simplify set to Maximum, it'll return a^2+2*a*b+b^2 automatically. If you have CAS Simplify set to either Minimum or None, tap the "simplify" button for the same result.

(08-25-2014 09:51 AM)sol740 Wrote:  3. It looks like a reasonable platform for data logging as well. Is there any StreamSmart documentation in context to the Prime? Ideally I'd like it to log temperature (300-400K) every 5 seconds for 2 hours, then be able to do some minor processing on it on the device (fourier analysis, stats)

I don't own a StreamSmart 410, but my understanding is that it is not a data logger, but a data streamer. This is important, because I don't think that you can tell it to do things like take one measurement every 5 seconds for 2 hours; it only sends a constant stream of data to the calculator, taking a zillion measurements in a very short amount of time, so that you can watch the phenomenon "live" on the screen. It can store and analyze that data, but it's not designed for discrete timed measurements. The user interface is totally interactive, not programmable, so you can't tell it what to do later and walk away. It's only for watching live demonstrations of measureable phenomena and analyzing the measurements of the phenomena which you just watched. At least that's how the StreamSmart 400 works on the HP 39gs/40gs/50g. If anybody here knows otherwise, PLEASE correct me!


RE: Couple of prime questions... - sol740 - 08-26-2014 09:10 AM

Thanks for your reply - much appreciated. Unfortunately I'm not getting any simplification or factoring on any CAS simplify operation or factoring:

[Image: kmXHiFM.png]

I'm in CAS mode. Sure I'm doing something stupid here but can't work out what it is.


RE: Couple of prime questions... - parisse - 08-26-2014 09:27 AM

Type a*b instead of ab. ab is a variable name with 2 letters, not the product of a and b.


RE: Couple of prime questions... - sol740 - 08-26-2014 09:33 AM

That did indeed work - many thanks!

I knew it was me being an idiot!

I was using a Casio FX-991ES PLUS which has only single letter vars before. It has brain damaged me a bit I think.

Changing the simplification settings worked as well. Sold!

Regarding data collection, I think I'll keep that external and PC based. I'd love to get rid of the PC from my workflow as there are so many distractions on it.