Explanation:
a restricting is only necessary, if we need to limit the x values or the y values for various reasons.
the limit for the x values are to eliminate any values that would create an invalid or otherwise undefined result.
otherwise the inequality itself establishes a restriction already.
e.g. sqrt(x) + 3 >= 1 would need an additional restriction
x >= 0 to know we can't even try small negative x to find out verify the solution.
something like
sqrt(x² + 3) >= 1 does not need any further restrictions, because we can use any value for x, from - infinity to +infinity. and the inequality will always be valid.
also consider, that the left side can never get smaller than sqrt(3) which is larger than 1. so, really everything goes.
we could say something like
sqrt(x² + 16) >= 5
we still don't need to give any additional restrictions, but the inequality itself rules out all x that are
-3 < x < 3.