Notation of the square (or other power) of a function $f(x)$

Question

How do you notate the square (or other power) of a function $f(x)$? Is it $f^2(x)$ (similar to $\sin^2(x)$ for example), $f(x)^2$ or do you have to use $(f(x))^2$?

Thanks in advance.

Answer 1

The standard way to write this is $f(x)^2$ (this always means $(f(x))^2$ rather than $f(x^2)$, so you don't have to worry about any ambiguity). You will occasionally see $f^2(x)$, but I would not recommend this--$f^2(x)$ more often means $f(f(x))$. The notation $f^2(x)$ for squaring $f(x)$ is generally used for only a few particular functions (typically ones that you might often want to square and whose argument is often written without parentheses), such as trigonometric functions and $\log x$.

Answer 2

Square of a function $f(x)$ can be denoted as $f^2(x)$, similar to $sin^2x$ and $cos^2x$.