Scientific calculators have XY buttons to allow for functions that involve powers and exponents. The XY button allows the user to multiply a number by a selected power.
Using XY Button

First input a number on the calculator, then push the XY button, then input the desired power. The calculator will give the result of the number and the power.
Powers, Exponents and Bases

The number you input first, before clicking the XY key, is the base number. It is multiplied by the exponent, or the number selected after clicking the XY key. The process of calculating base numbers by exponents is known as "raising to the power." In these calculations, the exponent is called the "power."
Calculating Powers

In math, the exponent is shorthand for repeated multiplication of the base by itself. In XY calculations the base represents the number and the exponent the amount of times the number will be multiplied by itself. For example: If 4 is the base number and the exponent is 3, the occasion would be 4 x 4 x 4, or 64, the equation can also be understood as 4 to the power of 3, also 64.
Why X and Y?

The symbols XY represent the common form of writing questions to do with calculating the power. For example, "2²," means the base number or X is two and Y or the exponent is also 2. In mathematics, unknown variables are represented by letters starting with x, y and z. The calculator is asking for the user to input the X and Y in an equation about powers.
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