Now that we have gone through single variable calculus and understand what calculus is about, it is time for us to go a step deeper and look at multivariable calculus. Multivariable calculus has a lot of similarities with single variable calculus, except—as the name suggests—here, we will be dealing with functions that accept two or more variables as input.
Multivariable calculus is used everywhere in the real world and has applications in every field and industry, from healthcare to economics, to finance, to robotics, to aerospace, and so on. An example of this could be trying to model how air curves around an airplane, to understand how aerodynamic it is and where the design of the airplane body can be improved. This is something we would not be able to do with single variable calculus.