HP 39G+ Graphing Calculator

Good. Product

this calculator is kind of confusing. it works but if you are taking a class that needs both radian and percentage, don't get this. it only comes in radian mode. besides that it is ok once you figure it out.

Calculators as the H.P. 49 II, H.P. 48 II, T.I. 89, or T.I. 92 are beyond the average high school or Junior Collage student's needs.Sad experience ... giving fancy, high priced, calculators to 10 year olds scares them into English majors or making french fries at a drive thru.The various `flavors' of the T.I. 83 and T.I. 84 have become the high school 'standard'.The 288 pages of documentation for this calculator are clearly written and straightforward. The subject is not at the level of complexity which has lead to some H.P. manuals and user guides being hard to read and understand. [The manual can be downloaded here.]In case you like technical comparisons of calculators there is one between the H. P. 39+ and the T.I. 83+ at the hpcalc.web site.This calculator has enough functions and capabilites, `out of the box' to carry many through Junior Collage. Its accuracy is greater than a T.I 83+. Its screen, larger than the T.I. 83+ ... is big enough for easy reading.At other stages of education other calculators, including several from T.I., are the best but for basic homeschooling in late middle school or high school for a kid who will never be a `geek' this is a fine, easy to use machine.Another group which this calculator is `perfect' is those, as I, who are retired from `semi - geeky' occupations and enjoy Number Theory, recreational math ... what some of the `high tone' folks at MIT and CALTECH call `Pop - Math' . And while very likely most of that math could be done on a $22 T.I. Scientific 36X Solar single line calculator [a really nice and useful ealculator] the H.P. feels better in my hand and anyway by buying a 39+ I am saving $30 over a 83+ or $40 over a 84+.

I'd recently bought an HP-49G+ and was terribly disappointed, both by its overall poor design and extreme complexity. I wasn't expecting much from the 39G+, but it really surprised me--especially given the low prices it's been going for lately.Inevitably people want to compare graphing calculators against the TI-83+ or newer TI models. While I have nothing personal against TI, I believe most of their calculators are significantly overpriced and underpowered. The main reason to buy one is because TI is the most popular in schools... and that's not a very good reason. (One obvious exception is the Voyage 200, because it has a QWERTY keyboard.)In terms of basic functionality (calculations, plotting/solving equations) the 39G+ works reasonably well. While I think some of the alternatives are easier to use (Sharp EL-9900C, Casio CFX9850 Plus) it offers a lot more functionality than most of the competition at the same price level. A fair question to consider is whether you want to make that tradeoff, because for day-to-day use I prefer using a simpler calculator like the Sharp or Casio, or an even simpler scientific.The 39G+'s most definite weakness is its screen. It's small, and the software doesn't make good use of it. Sharp's EL-9900C has a physically larger screen and uses it much more efficiently, especially when doing simple calculations. The 39G+ always keeps the current formula in a small area at the very bottom of the screen, which I find harder to read. On the other hand the 39G+ has a very nice keyboard; many will insist my comparison with HP calculators of yore is outright heresy, but it feels similar to me.The aplet idea is good but is hampered by a lack of dedicated hard keys and only so-so integration with the rest of the calculator. I found many common operations (zooming/windowing plots, for example) were less intuitive and required many more keystrokes than the other graphing calculators I've used. The symbolic solver/integrator/derivator is tricky to use, especially when using it from the HOME screen. But I do find the complete lack of the 49G+'s "equation writer" (more like "equation butcherer") a helpful convenience.Most modern calculators' user interface problems stem not from inherent bad design decisions, but simply from trying to include too much junk in too small a space with an inadequate hardware UI. The 39G+ is light-years better than the 49G+ because the functionality has been reduced to a manageable level... but I'm sure it could be shrunk even further without giving up much. When I need to do complicated math I'll use a computer with a real keyboard and display--it's faster, less frustrating, and more reliable than trying to type on a calculator with a tiny display, A-Z alphabetic keyboard, and no permanent storage."Which calculator is best" is a subjective question which truly depends on your level of experience, needs and expectations. For example, the 39G+ has better programming facilities than most other calculators, it's certainly possible to write efficient, solidly-integrated aplets on it. I couldn't care less! If I need to write a complicated program I'll do it on a computer; even the 9900C's limited abilities are more than enough for what I need from a calculator. But some users really want to write programs on their calculator, and for them the programming facilities are important. Someone else may need to do plots quickly, and for them speed is most important. (I have yet to see a good set of benchmarks comparing various calculators doing typical calculations.)For a toy or "mathematical exploration gadget" the 39G+ is a decent option. It doesn't have the horrible intricacies of a 49G+, but provides enough functionality to keep things interesting for a long time. The advanced programming features are a benefit here, it's a safe, easy-to-use environment which may stimulate an interest in learning how to do it "for real".I believe for most users the 39G+ is a reasonable choice at a reasonable price. If you need something with the TI label on it, obviously an HP isn't going to work (unless you pry off the label and replace it). If you really need advanced CAS or the like, I'd strongly recommend getting a laptop and installing Maxima/Octave/Euler/Maple/Mathematica/etc. If you want something simpler to use and don't need the symbolic algebra and programming features of the 39G+, consider a Sharp or Casio.

The Hp 39g+ is overall a decent calculator for you basic middle school and high school needs.--Pros-(1) The keys are plastic (finally) and much more stable.(2) The overall system is more stable and less prone to crash.(3) The Hp 39g+ has many more functions than the TI- 83+ (nearly 200 more) and when compared, it becomes overwhelmingly obvious that the 39g+ blows the Ti 83+ out of the water.(4) The Hp 39g+ is overall cheaper, and better for your money.(5) It can compute values up to the 499th power, while the Ti can only go to the 99th power.(6) It has a Root Solver on it, which basically allows you to solve algebraic equations (example: 2x^2=67/6+56= SQRT6*sin(5^45)(7) Less batteries are used in the Hp-39g+. Its three triple "A's" compared to four double "A's"(8) The 39 has a bigger screen with more contrast.(9) The Pretty Print option allows you to see equations in a form which they would look like in a textbook.--Cons-(1) The keys are noisy; they make an annoying clicking sound when on a surface.(2) The connection to a computer is somewhat finicky, and a large amount of the programs on various sites don't work on the 39g+ or are way too fast. That is because the old programs were designed for a much slower system.(3) Programs are essentially saved twice, so the same program as a TI on an Hp will be a lot bigger.(4) The lack of flash memory on the 39g+ makes programs less secure.Overall, the 39g+ is a great calculator and I highly recommend it.

I bought this for my 16 year old son and he loves it. It is a lifesaver for most AP courses in high school.