If$f(x) = x^n$, then$f’(x) = nx^{n-1}$.

Partial Differentiation

$$𝑢=[𝑓(𝑥,𝑦)]𝑛$$ $$𝑢_𝑥=𝑛|𝑓(𝑥,𝑦)|^{𝑛−1}\frac{∂𝑓}{∂𝑥}$$ and $$𝑢_𝑦=𝑛|𝑓(𝑥,𝑦)|^{𝑛−1}\frac{∂𝑓}{∂𝑦}$$