in general, given two numbers formula_1 and formula_2, the exponentiation of formula_1 and formula_2 can be written as formula_5, and read as "formula_1 raised to the power of formula_2", or "formula_1 to the formula_2th power". other methods of mathematical notation have been used in the past. when the upper index cannot be written, people can write powers using the ^ or ** signs, so that 2^4 or 2**4 means formula_10.