$\pm 1$

$-2$

$-1$

1

${(-5)}^0=0$

$x^2+x^3=x^5$

${\left(a{b}^2\right)}^3=a^2{b}^5$

$2a^2·a^{-1}=2a$

$1-\frac{1}{x}$

$\frac{x^2-1}{x}·\frac{x}{x+1}$

$\frac{x+1}{x}÷\frac{1}{x-1}$

$\frac{x^2+2x+1}{x+1}$