Tin foil tin taste to food wrapped in it, which is a major reason it has largely been replaced by aluminium and other materials for wrapping food. Because of its corrosion resistance, oxidation resistance, availability, low cost, low toxicity, and slight malleability, tin foil was used as a filling for tooth cavities prior to the 20th century. The first audio recordings on phonograph cylinders were made on tin foil. Tin foil Tin foil, also spelled tinfoil, is a thin foil made of tin. Actual tin foil was superseded after World War II by cheaper and more durable aluminium foil, which is still
FOIL method FOIL method In elementary algebra, FOIL is a mnemonic for the standard method of multiplying two binomials—hence the method may be referred to as the FOIL method. The word "FOIL" is an acronym for the four terms of the product: The general form is: Note that is both a "first" term and an "outer" term; is both a "last" and "inner" term, and so forth. The order of the four terms in the sum is not important, and need not match the order of the letters in the word FOIL. The FOIL method is a special case of a more