Watch the documentary 'Enron: the smartest guys in the room'. It gives a good impression of the kind of handwavy math is being applied, thinking that the truth wouldn't eventually catch up. Then, knowing this, have another look at economics, and try to understand it without the fancy tricks such as the ones described in that documentary and e.g. documentaries on the mortgage crisis.
Once you get the basics, you'll find that all of the more complicated tricks are all forms of delays and indirection that try to make things work that shouldn't work in the first place. (Or forms of trade-offs between parties.) However complicated things get, there are basic underlying rules that must hold for things to remain sound and correct.
The "complicated rules" of economics don't change the inner workings. They merely add delays, indirections, etc., as-if traveling not on the shortest most direct route, but instead a suboptimal route with loops and awkward bends and directions.