5. The expression is $1 \div[1 \div x-1 \div(x+1)]-x$, or $1 \div[1 \div(x-1)-(1 \div x)]+x$.
5. Given $x(x \neq 0, \pm 1)$ and 1, if only addition, subtraction, and division with 1 as the dividend are allowed (parentheses can be used), and it takes six steps to calculate $x^{2}$, then the expression for the calculation is $\qquad$ .