I am going to be taking Calculus III and i need one more math class afterwards. I was just wondering if anybody could suggest which one I should take? Thanks.

I am going to be taking Calculus III and i need one more math class afterwards. I was just wondering if anybody could suggest which one I should take? Thanks.
It depends on what you are interested in and what your career goal is. Also what are the options available?
I am a bio major. I took AP calculus BC and opted out of Calc I and II but I need to take two math classes still. Some of the options include linear algebra, set theory and logic, advanced probability theory, diffrential equations and advanced calculus to name a few.
Make sure Lin Alg is one of those courses!
What exactly does linear algebra entail?
If done correctly you will study linear transformations of vector spaces, but often a first couse will focus just on solving systems of equations and getting you used to dealing with matrices. It underpins a lot of useful mathematics, including calculus.
You may want to look inot the probability theory classes as well.
Differential equations is a useful class and is applicable to a lot of natural sciences, including biology. Not sure about yours but I know that some universities teach a version of it as a single class along with linear algebra. If not, linear algebra can be particularly useful if you plan on doing computational biology or programming at all in your career. I know that probability has a number of applications to biology as well. I suppose it really just depends on where your own personal interests lie, and how you plan to use your degree upon graduation.
If you haven't taken Discrete Mathematics, its one of the most fun math courses out there. Its kind of a catchall of logic, probability, proofs, and other stuff that's useful for programming.
Sadly, if you are a Bioscience major, then Probability Theory will be more useful to you. I say sadly as it is extremely boring.
But if you want to have fun, and have a limited knowledge of calculus, I suggest Linear Algebra  it deals with vector spaces, linear operators and matrices. It is a lot of fun, is not too hard (i.e. is largely intuitive) and requires almost no prior knowledege.
Plus the subject is extremely important in all exact sciences
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