If x

B obviously doesn't take any value for X. If 3 is taken, then as long as n> formula 9 doesn't hold.

Because there is no maximum value of x square in d, no matter how big x is, n can be found, so n >；; The square of x, so it is wrong to use any n here.

As for the original proposition, because there is no maximum value of x square, no matter how big x is, n can be found, so that n≥x square is true.

Because they all exist in C, such as x=4 and n= 12, the formula holds.