Oftentimes, one can avoid having to memorize in math if the underpinnings of a given process are understood. This is always the preferred method, however, for convenience there are many formulas that are used to make solving problems simpler without having to recreate the wheel each time. Below are some techniques you may find useful. Feel free to comment if you have additional techniques you'd like to share.
1. Whenever you are solving a problem that requires a formula - write the original formula down in it's entirety without immediately substituting in values for the variables. After doing problem after problem this way you will have inevitably impressed the formula into your memory banks.
2. As mentioned in a previous post, you can always go the flash card route. Write the formulas on 3x5 cards, put them in your pocket or backpack and go over them multiple times throughout the day until you've got them down.
3. You can repeat the formulas out-loud over and over again so you are audibly hearing them repeated. Some people learn better by seeing, others by hearing.
4. Maybe you are more of a tactile learner. You could trace with your finger or your whole hand the formula in the air or on the table. If it is a geometry formula involving a shape you could make a 3 dimensional replica and hold and look at it from every angle while seeing each dimension required in the formula.
5. Perhaps you are artistic and like to make a little rhyme, song, or rap of the formula to help you remember it. I've had students sing me so many different renditions of the quadratic formula that I'm always amazed...and it works.
In conclusion, I'd just like to say that if necessity is the mother of invention then repetition(which all the above techniques require) is the daughter or granddaughter. Mathematicians created these formulas and we are now learning to appreciate, learn and use them. And hopefully some of you will go onto discover new ones as well...and p.s. you get to name the formula whatever you like...or name it after yourself if that suits you!
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