The set $\mathbb{R}^{\nvDash}$ is used in my multivariable-calculus assignment, but I do not know what the superscript '$\nvDash$' means on the set of real numbers. The context in which it used is that a curve lies in set domain and I must evaluate its line integral.
Thanks!
-Bryan
As mentioned in a comment, this is in all likelihood the result of a typo:
\mathbb{R^2}(instead of\mathbb{R}^2) can produce what you see. Other exponents like 1, 3, 4 would produce similar but distinct things.