I am currently in high school and is writing a maths research paper on a calculus problem. In the conclusion, I would like to include a 3D plot of a function I found. It goes something like this: 
a, b, are constants and m is the first positive solution to the equation.
So far I have Matlab available though I've never used it before. Just looking for some pointers into how would I plot this function.
On
First, before seeking help, you should provide some demonstration of how you'd like to approach the problem. In this case, what are some valid techniques you can use? The function appears at first glance to not be continuous and will have a lot of jumps.
Graphing in Matlab is pretty easy, so once you come back with a strategy of what you'd like to graph and how to graph it, we could graph it for you. Good luck
When @bloodtypebpos uses the term "strategy", he may think the same thing as me; the most important feature of your problem is that you have a transcendental equation to solve many times (first strictly positive root of $t-tan(t)=a$ in order to get $t=f(a)$). The main idea, for an efficient programming, is to tabulate first (using matlab's "fsolve") the values of this function $f$ with a reasonable degree of accuracy and on a reasonable range. Then use this table whenever you need a value. Plotting is definitely not the problem...