Just gotta prove that $$g(v,w) + n \otimes n (v, w) - g(df(v), df(w)) = 0$$
What's the formula for $n$, is it just $df$
You got like $n \otimes n(v, w) = n(v) \cdot n(w)$ right?
Wait no, the second metric is the wrong space
It's too late for diff geom