How does one raise one's self?

Calculus Level 1

$\begin{aligned} 1^1 &=& 1 \\ 2^2 &=& 4 \\ 3^3 &=& 27 \\ 4^4 &=& 256 \\ 5^5 &=& 3125 \end{aligned}$

Victoria just started learning about exponentiation in class, and she has written down the 5 equations above. She then postulates that

$x^x$ is a strictly increasing function for positive $x$ .

Is her claim correct?