There are many mathematical formulas, and it is really not easy to remember each one clearly. Always remember this and forget that, how can I remember it better? This is really a difficult problem. However, still have to solve, that is:

First, remember in understanding. Understand the background of a formula, and then remember the formula. For example, you should be able to deduce arithmetic progression's summation formula by yourself and do an example. As far as this formula is concerned, arithmetic progression can also be visually regarded as a ladder, like a trapezoidal area formula.

Second, carry more. Only read more and remember more. This is the most basic principle, which is universally applicable. The point is one word "many".

Third, remember to understand the formula in the question. Never "don't do simple questions, don't do difficult questions", just do simple questions, in order to remember the formula. To be precise, you can't always turn over the books.

Fourth, talk about some skills. For example, the inductive formula in trigonometric function really needs to understand the meaning of the bold font in the book.

Fifth, write all the formulas on a piece of paper card, put it on the bedside and read it before going to bed. This is a concrete and good way. Never give up.