2. If $f(x)=\sqrt{2-x}$ and $f(g(x))=\sqrt{2-x^{\prime}}$, then what is $g(x)$ ?
\(\boxed{g(x) = x^\prime}\)
Step 1 :Given that $f(x) = \sqrt{2-x}$ and $f(g(x)) = \sqrt{2-x^\prime}$, we need to find the function $g(x)$ such that $f(g(x)) = f(x^\prime)$.
Step 2 :Substitute $g(x)$ into $f(x)$: $f(g(x)) = \sqrt{2 - g(x)}$
Step 3 :Since $f(g(x)) = \sqrt{2 - g(x)}$ and $f(x^\prime) = \sqrt{2 - x^\prime}$, we can equate the two expressions: $\sqrt{2 - g(x)} = \sqrt{2 - x^\prime}$
Step 4 :Comparing the two square roots, we can see that $g(x) = x^\prime$
Step 5 :\(\boxed{g(x) = x^\prime}\)