Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Preventing my Math skills from becoming rusty

  1. Nov 19, 2011 #1
    Hey everyone!

    I'm deciding whether to major in Economics, Business Finance, or Chemical Engineering, and what I know about the three is that they all require plenty of knowledge in mathematics (Chem. Engineering especially). I wanted to take Calculus 1 next semester, but my couselor suggested that I take it easy next semester because of my problems with stress, and told me to take a course in Critical Thinking instead.

    My question is: to prevent my skills in Precalculus from becoming rusty, would it help if I buy myself both a used Trigonometry and Precalculus textbook? Or what else could prevent my preparations for Calculus from fading?
  2. jcsd
  3. Nov 19, 2011 #2


    User Avatar
    Science Advisor

    Hey Bogrune.

    I think the most important thing in mathematics is to understand the key ideas.

    In most mathematics courses there are a few main key ideas that set the foundation for the rest of the course.

    Take for example calculus. Calculus is the study of change. One main idea in calculus is that you can calculate different measures like area, volume, length, flux and so on analytically for large classes of objects. The key thing though is not the actual equation, what it represents. When you are able to understand how things are actually changing with respect to whatever else, it becomes a lot easier to not only realize what an existing integral/differential equation etc represents, but also how to construct various formulas for things like length, volume, area and so on.

    Again, if you understand what the differentials, derivatives and integrals are referring to, that is the most important thing. You will probably not remember all of the substitutions and tricks off by heart, but then again many people don't unless they use it on a semi-regular or regular basis.

    Also with regard to the critical thinking class, I don't know if its a waste of time or not, but in terms of critical thinking, be critical of everything you hear no matter who tells you, but keep an open mind and consider all that is out there. It sounds paradoxical but its hard to find any absolute truth in the world no matter what field we are talking about, so you need to be open to new ideas as well as on your guard for not blindly accepting them.

    Maybe you do the class you could also critically assess your teacher and give them a run for their money.

    Also remember that everything wont make sense all at once. Sometimes it comes instantly and sometimes it doesn't.
  4. Nov 19, 2011 #3
    It's not that I'm taking the class because I want to, but because it's a general ed. requirement. I'm still deciding whether to take it as Literature or as Philosophy.

    Still, thanks for the advice. I'm just concerned about my skills in Trigonometry and wtih Matrices because I kept hearing that both topics will be crucial in Calculus III and Linear Algebra.
  5. Nov 19, 2011 #4
    How long ago did you have Trig and Precalc, and how well did you do?

    While tutoring calculus the biggest issue I see with calculus students that have taken a small break is they just forget algebra stuff more than some of the specifics in precalc. Do you remember your properties of logs/exponents/roots? Can you factor a binomial and use the quadradic formula? The specific things you covered in precalc like finding limits and asymptotes likely is covered again, with a different mindset, in Calc I (so having a basic knowledge of the concepts from earlier is all you need).

    I would say that even semester-to-semester most students lose the trig-identities (which is OK, since most calc books have a table in the covers/appendex to reference double angle and squares when neccessary), but it would be important to know the trig functions themselves.
  6. Nov 19, 2011 #5


    User Avatar
    Gold Member

    Have you ever considered tutoring? It's another option for consideration.
  7. Nov 19, 2011 #6
    trig and precalc have nothing to do with what you cover in calc, and the things you might have seen from there, they will go over again.

    just make sure to review your algebra/fractions/logs/exponents a few days before class starts.
  8. Nov 19, 2011 #7
    Have you tried viewing Khanacademy? I think it might fit your needs (more intuition than solving problems) and it even has calculus explained at a high school level so you could get a head start.
  9. Nov 20, 2011 #8
    Or you could just check out a calculus book from your library and start studying that during your free time
  10. Nov 21, 2011 #9
    You know, that's just what I kept thinking to myself over the past few weeks! All I know about Calculus so far is the basics of limits (i.e. (f(x)= 1/x) y=0 as x→∞).
    Guess that means I should review polynomial factoring and division some more then. Should I also review partial fractions as well?
    Last edited: Nov 21, 2011
  11. Nov 22, 2011 #10
    Partial fraction decomposition should be 'retaught' enough for you to catch on. It has more integrations usage, so you probably don't need to worry about it as much until you get to Calc II.

    But polynomial factoring and your 'basic' algebra operators (log, exponents) should be second nature, if you're going to be successful. Don't worry about synthetic division of polynomials. Anything of order > 2 will be easilly factorable (eg: x^5-16x can be very easilly factored by chaining difference of squares a few times).
  12. Nov 22, 2011 #11
    I would agree with that. The most common problem I see when I tutor freshman in calc 1 classes is that they have completely forgotten basic algebra.

    Basically you want these skills to be second nature so that you can focus all your attention on the problem at hand.

    As far as trig goes, it is useful to know the properties of the functions as well as the common identities, both of which can be found in most standard calculus books.

    Finally, in regards to matrices you should just know how to add, multiply and take the determinant, everything else should be covered in your linear algebra course
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook