Economic models that are useful to understand macroeconomics

Question

I started to study economics. Since I majored in Mathematics, I'd like to learn the principles of macroeconomics through the analysis of a simple economic models (using equations). That's why I looking for a book that teaches some simple economic models.

My question is: which book teaches about a simple economic model that presents concepts like GDP, aggregate demand and supply curves, inflationary gap, demand-pull inflation, diminishing returns, etc?

The materials that I found don't explain very well some equations. For instance, they usually use the variable $Y$ for aggregate output, but also uses variations $Y_a$, $Y_d$, $Y_p$ to denote disposable person income, disposable income, and potential GDP, respectively, without explaining the difference between those concepts.

Thank you for your attention!

Answer 1

If you look just for a simple mathematical models you can have a look at Blanchard et al Macroeconomics European Perspective. It covers all the concepts you mention perhaps with exception of diminishing returns because that is more general economic concept that you might already be expected to know before dedicated macro class. You can also have a look at Mankiw Principles of Economics, it has both micro and macro at undergraduate level. However, if you come from math background you will find undergraduate models perhaps too simple.

If you have good grasps on calculus and differential equations then something like Romer Advanced Macroeconomics will be perhaps more interesting to you even though its less simple.