# How to read this formula aloud: “f(x) = x²”?

f(x) = x2

Having heard this read only in Korean, I don’t know how to read it in English. What is the right English reading?

• You can find a pdf-file called How to pronounce mathematical formulae in English in various places on Internet. (I was not sure, which site is most reliable and most probable to last for a long time, so I've linked to a google search instead.) – Martin Jun 7 '14 at 15:29

It would normally be read aloud as:

f of x equals x squared

There are some variations you might hear. For example, sometimes is is used in place of equals.

If the exponent was 3, you would say cubed. Anything higher than three (say, for example, 5) would generally be read aloud as:

f of x is x to the fifth (power)

or perhaps:

f of x is x to the power of five

• You can read x^4 as "x tesseracted". But okay, hardly anyone does. :-) – Jay Jun 3 '14 at 13:40
• Some people say "f at x" instead of "f of x" – Max Jun 3 '14 at 16:28
• @Max That's usually used for a constant: "If f of x is x squared, then f at 3 is 9." – Ypnypn Jun 3 '14 at 19:02
• "to the power of" is the general form here - it's appropriate for any exponent, including fractions. The other versions are all short forms for (specific) whole numbers. – Brilliand Jun 3 '14 at 19:45
• @Brilliand - I agree. Moreover, the words "power of" are sometimes omitted for the sake of brevity, as in: "x to the two-thirds" or "e to the i pi". – J.R. Jun 4 '14 at 1:04

f(x)=x2 is simply read as f of x equals x squared. f being the function name and x being the input and x2 serves as the output. https://www.mathsisfun.com/sets/function.html