Do I need to know this formula for GRE Algebra?

[valkener]

I guess this is for more advanced quatratic equations. Do I need to add this to my "must remember" list?

Also, if anyone has a list of algebra formula's and/or GREMath formulas in general that one should know let me know :-).

(I understand that for geometry, for example, this is important and less important for problems where u can plug in.)

[psychdork]

I took the GRE the other day and scored in the mid-700s (old scoring version). All of the polynomials I was given I was able to solve simply by factoring them, so as long as you can do that, then I wouldn't worry about memorizing the quadratic formula. I'm pretty sure the GRE quant books I skimmed never went into using the quadratic formula.

I'll have to think about what formulas came in handy but off the top of my head definitely make sure you know:

-area & perimeter of a square and rectangle

-area of a triangle (including how to solve for 45-45-90 and 30-60-90 triangles

-area and circumference of a circle

[buffbulls4588]

I'm assuming you're not a math/engineering major? If you are it's ok too, the range of questions that could pop up on the GRE is pretty wide. Depending on when you plan to take the GRE, you should just do as many practice problems as possible, and if you have time, before you even begin to practice, purchase a study guide for something around $25-$40 and go through their quantitative review. The Kaplan GRE prep book does a pretty good job. I never ran into a situation where I had to use the quadratic formula and I did over 300 practice quantitative problems from the Kaplan book in one week, as well as the 80 extra I took on the powerprep tests. Then again if I did run into a situation where I had to use the quadratic I probably would have recognized it, if you're not an engineering or math type of major then it's understandable, it's a pretty simple formula to memorize, whether you have to memorize it or not I'm not sure, sorry that I couldn't be of more help. One thing I can say is make sure you know all of the equations for area for basic shapes, such as circles which pop up a lot, and obviously your squares, rectangles and triangles.

[rockbender]

You probably won't need it. If you can remember things really quickly, then sure put it on your "to remember" list, just in case. But to be honest - most math problems on the GREs have little "tricks" that you can use to solve them. For example, a problem that might look like it needs the quadratic equation might be easily solved by process of elimination.

http://www.ets.org/gre/revised_general/prepare/quantitative_reasoning Check out the ETS page on the math section. They explain the 4 different types of questions and offer math review and conventions PDFs at the bottom. I think you would be better off learning as many of the "tricks" as possible, rather than trying to memorize complicated formulas. These "tricks" are covered in just about every GRE practice book. I know those books are expensive, but you might be able to borrow some from a library. I borrowed 4 books (Barons, Kaplan, Peterson's, ETS) from my library and they were super helpful with the "tricks" and tons of practice questions! I highly recommend using a book to study for the GREs, especially the math section. Peterson's and ETS were the better ones.

Good luck!

[Instigate]

If I were you I would memorize it. Sure as the other posters say you can always use other tricks to solve the equation, but the problem is which one is faster. Sometimes you dont see the trick right away, or you get stuck on the factoring out and is much faster to simply plug in the numbers for the formula. Plus it is an easy formula, wont take much time to memorize!

[valkener]

Thanks guys, I have Manhatten coming in the Mail (8 Book Series) and am currently using Magoosh. However, both of these materials focus on high-scoring through brutal methodology. I'm going to have to focus on tricks soon as this might be more helpful and faster in the end. I will also try to do as much practice as possible. Anyway, thanks!

PS: One more question: How about 3 equations with 3 unknowns? Did any of these ever pop up?

Edited October 14, 2012 by valkener

[kaykaykay]

Thanks guys, I have Manhatten coming in the Mail (8 Book Series) and am currently using Magoosh. However, both of these materials focus on high-scoring through brutal methodology. I'm going to have to focus on tricks soon as this might be more helpful and faster in the end. I will also try to do as much practice as possible. Anyway, thanks!

PS: One more question: How about 3 equations with 3 unknowns? Did any of these ever pop up?

I am a foreigner and this is elementary school math where I came from.... I am sorry.... I want to be constructive. ....The math section in the GRE is not difficult but I feel that you will not get through it without studying. Just sit down and do the math section of one of these books & practice. Some books will give you a sheet of useful formulas that you can study. ... not even a lot. We all want this to be easy but on some level this is an entrance exam. (testing in my opinion how well you can swallow sitting down and studying)

good luck!

[valkener]

I am a foreigner and this is elementary school math where I came from.... I am sorry.... I want to be constructive. ....The math section in the GRE is not difficult but I feel that you will not get through it without studying. Just sit down and do the math section of one of these books & practice. Some books will give you a sheet of useful formulas that you can study. ... not even a lot. We all want this to be easy but on some level this is an entrance exam. (testing in my opinion how well you can swallow sitting down and studying)

good luck!

Clearly, Algebra is high school and not elementary. Polynomials are usually not included in the GED though they might. They are on the GRE. I am also a foreigner so I know that solving 3 Equations with 3 Unknowns is not elementary school math. Anyway, I'm just trying to narrow it down. I am studying about 2-4 hours every day. Good luck to you too.

[Darth.Vegan]

You definitely don't need it.

[iowaguy]

That formula is in the official GRE study guide, so it could certainly show up on your test, especially on your 2nd "harder" section (assuming you do well on the 1st section). Usually though, quadratic equations on the GRE can be factored... In the 2 ETS Powerprep practice tests there aren't any quadratics that need factored, for example...

[Darth.Vegan]

According to Barron's online GRE prep, all quadratics on the GRE can be factored.